^j^ysf^j-^-^i-p ^ QL 533.4 B86 1906 ENT r/i "Mil m '■ Z:"^-' ■^'^ BnV'^^ Ifvii^n^ (AJAfu/^^l H'S-^^y/J. h^t h ^^/g^ ILLUSTRATIONS OF BRITISH BLOOD-SUCKING FLIES. WITH NOTES BY ERNEST EDWARD AUSTEN ASSISTANT, DEPARTMENT OV ZOOLOGY, BRITISH MUSEUM (n.H.; LONDON PRINTED BY ORDER OF THE TRUSTEES OF THE BRITISH MUSEUM SOLD BY Longmans & Co., 39, Paternoster Row, E.C. B. QuARiTCH, 15, Piccadilly ; Dulau & Co., 37, Soho Square, W. Keoan Paul & Co., 43, Gerrard Street, W. and AT THE British Museum (Natural History), Cromwell Road, S.W. 1906 .-/// riL'/Us irsi:rvi:d c.':i;uH3i.j/^y~ LONDON. WITHEKBY & CO., LKIIEKPKESS AND COLOUR PRINTERS, 326, HIOM IIOLBOKN. CARDED DIV. OF HTSSCW PREFACE. 'TpHE coloured drawings from which tlie phites in this book are reproduced have been prepared for exhibition in the North Hall of this Museum. Before devoting them, however, to the purpose for which they were primarily intended, it was thought that if published in a con- venient form their sphere of usefulness would be increased, while an opportunity would also be afforded for the inclusicDn of fuller notes on each species than can be given in a label. For exhibition purposes, and to facilitate the recognition and comparison of the different species, the drawings have been made on a greatly enlarged scale, to which it has not in all cases been possible to adhere in the reproductions ; but wherever practicable the copies are of the same size as the originals. Many of the species here illustrated ha\-e an extremely wide dis- tribution, so that the book may perhaps be of service to naturalists outside the British Islands ; while the illustrations, either as repre- senting species or simply as types of genera, will doubtless be useful to those engaged in the study of Blood-Sucking Flies in connection with disease. E. RAY LANKESTER. British Museum (Natural History;, Cromwell Road, London, S.W. March 24///, 1906. LIST OF PLATES.* CHIRONOMID^. Mwc.es. Plate I. Fig. i. Ceratopogon varius, Winn. Plate I. Fig. 2. Ceratopogon pulicaris, Linn. CULICID.'E. Gnat.s or Mosquitoes. Plate 2. Anopheles nigripes, Staeg. Plate 3. Anopheles bifurcatus, Linn. Plate 4. Anopheles maculipennis, Mg. (The Spotted Gnat.) Plate 5. Theobaldia annulata, Schrk. Plate 6. Ciilex cantans, Mg. Plate 7. Culex nemorosiis, Mg. Plate 8. Culex pipiens, Linn. (The Common Gnat.) Plate 9. Grabhamia dorsalis, Mg. SIMULIDtE. Plate 10. Simulium reptans, Linn. TABANID.^. HOR-SE-FLTES. Plate II. Fig. i. Hrcmatopota pluvialis, Linn. Male. Plate II. Fig. 2. Ha;matopota pluvialis, Linn. Female. * Except where otherwise staled, the female alone is Illustrated. The crossed lines on the plates indicate the natural size of the insects. Plate 12 Plate 13 Plate 14 Plate IS Plate 16 Plate 17 Plate 18 Plate 19 Plate 20 Plate 21 Plate ■■yy Plate 23 Plate 24 Plate 25 Plate 26 F'k'- Plate 26 Fig. Plate 27 Plate 28 Hrematopota crassicornis, Whlbg, Tlierioplcctes micans, Mg. Therioplectes montanus, Mg. Therioplectes luridus, Fin. Therioplectes tropicus, Pz. Jaenn. Therioplectes solstitialis, Schin Atylotus fiih-us, Mg. Tabanus bo\inus, Lw. Tabanus sudeticiis, Zlr. Tabanus autumnalis, Linn, Tabanus autumnalis, Linn Tabanus bromius, Linn. Tabanus maculicornis, Ztt. Tabanus cordiger, W'ied. Chrysops cascutiens, Linn. Chrysops crecutiens, Linn. Chrysops quadrata, Mg. Chrysops relicta, Mg. form bisignatns. Male. Female. Male. Female. Plate 29. Plate 30. Fig. i. Plate 30. Fig. 2. MUSCID^. StomoxNs calcitrans, Linn. Ha;matobia stimulans, Mg. L}-]iernsia irritans, Linn. Plate 31 Plate 32 Plate 33 Plate 34, Plate 34 Fig. I. Fig. 2. HIPPOBOSClDzE. Hippobosca equina, Linn. (The Forest Fly.") Ornithom)-ia axicularia, Linn. Lipoptena cervi, Linn. Male. Lipoptena cer\i, Linn. I'cmale. Melophagus (n'inus, Linn. (The .Sheep " Tick.") INTRODUCTION. THE British entomologist desirous of obtaining' coloured illustra- tions of his country's insect fauna finds that, as regards the more popular Orders, such as the butterflies and moths, or the beetles, ample provision has been made for his wants. Should his predilections, however, incline towards Flies (Diptera), the case is altogether different. For, with the exception of the excellent coloured figures of certain British Diptera contained in Vol. VIII. of Curtis's ' British Entomolog}'' (man\- of which were published more than eighty years ago), and three plates of equally excellent coloured figures included in Miss Staveley's ' British Insects ' (London : L. Ree\-e and Co., 1871), no illustrations of British Flies in colour are obtainable. It is hoped that the plates in the present work, which faithfully depict the natural colours, and man}' of the external structural characters of some of the most interesting and important of Britisli Diptera, may do something towards meeting the deficienc}-. Although under the social conditions of modern life Blood- Sucking Flies are less troublesome to human beings in the British Islands than in some other less highly civilised countries, many of the species illustrated in this book still often contrive to make their presence inconvenienth- felt, while others in country districts are regular tormentors of cattle and horses during the summer months. Within the last few years Blood-Sucking Flies ha\e acquired a new- importance, in view of modern discoveries as to the causation and dissemination of certain diseases of man and animals, and although no Blood-Sucking Fl)- is permanently associated with any disease in the British Islands at the present da\', the British mosquitoes of the genus Anopheles remind us of the time, still comparati\-ely recent, when ague was rife in England, while Stovioxys calcitrans recalls the Tsetse-flies of Tropical Africa, and the part played by them in sleeping sickness and nagana. 8 In the followinc^ passes no attempt has been made to suppl)" a detailed technical description of each species illustrated in the plates. In the case of the majority of the species, at an\' rate, it is beliexed that the plates will render such descriptions unnecessary, and, apart from this, the man\- demands upon the author's official time would have made their preparation impossible. The same reason, coupled with limitations of space, has also unfc^tunatel}- necessitated the omission of a considerable amount of matter relating to the life- history of the species mentioned, but brief notes on life-history are included in the remarks upon each famih'. Since it was thought that British readers might be interested to learn in what other countries our native Blood-Sucking Flies are found, the geographical distribution of each species so far as it is known has in all cases been stated. References to original descriptions of genera and species, and discussions of synonj-ni}-, though nccessaril}- included in a monograph, have here been omitted as out of place in a work which does not profess to be more than a popular account of the insects of which it treats. Since the [jrimarj- object of this book is to facilitate by means of the plates the identification of Blood-Siicking Flies, the males that (probably with the exception of those of species belonging to the Muscida; and Hippoboscidre) do not suck blood have not, as a rule, been illustrated. The original water-colour drawings of the species represented have been prepared b}- Mr. A. J. Engel Terzi with his usual care and exceptional skill, and a word of acknowledgment is also due to Mr. Harry F. VVithcrby (of Messrs. W'itherby and Co.), who has personally supervised their reproduction, and has been unremitting in his endeavours to produce thorough!)- satisfactory copies of the artist's beautiful work. A special feature deser\ing of note in connection with the illustrations is the use oi periiuiiicut paper for the plates, instead of the perishable coated paper generally emplo\-ed for three-colour work. The change has greatly increased the difficulties of reproduction, but it is hoped that it will be appreciated by purchasers of the book. Field notes on many of the species illustrated and mentioned in the text have been kindly contributed by Lieut.-Colonel J. W. Yerburj', an enthusiastic collector and student of Diptera, to whose generosity the Museum is largely indebted for its modern collection of British Flies. ERNEST E. AUSTEN. British Museum (Natural History), London, S.W. March 2\st. 1906. BRITISH BLOOD-SUCKING FLIES. IN the shape of the common house-fl_\', or the bhie-bottle, Flies are familiar to ever_\-one, and a brief examination of either of these household pests will re\eal two of the chief characteristics of the Order (DipteRA) to which they belong, — the possession of but a single pair of tvings, and, immediately behind these, the presence of a pair of little knobbed organs, the lialteres or balancers, which represent the second pair of wings possessed by other insects. These two features, — the single pair of wings and the halteres, both of which can clearly be seen in the majorit}- of the plates illustrating the present work, — serve to distinguish all ordinary Diptera from all other insects. The winged males of Coccidre (Scale-insects), which belong to the Order Rh\-nchota, though they have only one pair of wings, and might perhaps be mistaken for gall-midges (Diptera), are distinguished by the possession of a pair of long caudal filaments at the tip of the abdomen, and by being without halteres. In a small number of aberrant Diptera, as in the sheep " tick " (Plate 34), the wings, or both wings and halteres, are entirely wanting, but in these cases the other details of the insect's external anatomy disclose its systematic position. Under the term " Flies " we include then, not only the horse-flies (Tabanidje) and many other families, the species of which more or less resemble the house-fly in shape, but also the midges and mosquitoes, which, though very dissimilar from the former in appearance, nevertheless possess all the essential structural characters of Diptera. Excluding the Fleas (Pulicid.t), which it is better to regard as forming a separate Order of insects, 59 families are recognised in Verrall's 'List of British Diptera,' 2nd Edition, (Cambridge, 1901). Of these, if we leave out of the question the highl)- specialised and 12 extremely aberrant Xycteribida;, which, doubtless, suck blood, but, being exclusively parasitic on bats, are of no practical importance, the blood-sucking habit is met with in only eight. Included in this total are the Psychodidae and Leptidse ; as regards the former, the blood- sucking genus Plilebotoinus does not occur in Great Britain, and although blood has been noticed (by the Rev. A. E. Eaton) in the abdomen of a British specimen of Sycorax silacea, Hal., the insect has not j'et been observed in the act of sucking blood, so that for our present purpose the Psychodida; may be left out of account. The same course may be taken in the case of the Leptida;, for no species of this family has yet been recorded as sucking blood in the British Islands, although in France the common British Leptis scolopacea, Linn, (as also L.strigosa, Mg. — a " reputed " British species) has been observed in the act of doing so on two or three occasions. The number of families of British Diptera that include blood-sucking species is therefore reduced to six, — the Chironomida; (midges), Culicidaj (gnats or mosquitoes), Simulid.c, Tabanidiu (horse-flies), Muscida;, and HippoboscidcX-. In two of these, the Chironomida; and Muscida', the blood-sucking habit is exceptional and confined to a few species ; in the remainder, with the exception of a few small genera of Culicidae, the species of which do not suck blood, it is universal in the female sex, to which, with the exception of the Muscidai (and possibly of the Hippoboscida:), the habit is restricted. It should be noted that most, if not all, mosquitoes are also capable of subsisting upon the juices of plants. The number of species of blood-sucking flies that occur in the British Islands cannot be stated precisely, since the total of the blood-sucking species of midges(genus Ceratopogon,sc>is.lnt.)7iX\d that of our indigenous species of Simttliuni is at present entirely uncertain. If, however, we count each of these groups as numbering a dozen species (certainl)- not an extravagant estimate), and include the two species of Nycteri- bida;, the number of British species of blood-sucking flics would amount to 74. The total number of species of Diptera recognised as British at the present time may be taken as between 2700 and 3000. With these introductorj' remarks we may proceed to a consideration of the species illustrated in the plates, which represent the principal British blood-sucking flies. 13 Family CHIRONOMID/E Midges. Although these insects are by far the smallest of all blood-sucking flies, the pertinacity and blood-thirstiness of some species of midges is such that, in the British Islands at any rate, they cause much more discomfort and annoyance to human beings than the species of any other family mentioned in this book ; and, during the spring and summer months, in the evening hours when they are most active, their presence often constitutes a serious drawback to life in the country. Occasionally midges occur locally in such numbers as to amount to a veritable plague. With reference to a species, at present un- determined, which abounds in Scotland, Colonel Yerbury writes : " This insect is a great pest in the Highlands ; it collects in large numbers on one's knickerbocker stockings, and the bites cause the skin to look as if covered with a severe rash." It should be pointed out that the majority of the species of midges are perfectly harmless. The British blood-sucking forms belong to the genus Ceratopogon {sens, lat.), which is distributed throughout the world, and of which we have some fifty indigenous species. Only a few of these, however, are known to suck blood, and the habit is confined to the female sex. As in the gnats or mosquitoes (Culicida^), the wings when at rest are carried flat, closed one over the other like the blades of a pair of scissors ; in many species (as in the two selected for illustration) they are minutely hairy, and they are often speckled with greyish brown blotches. The sexes can be distinguished owing to the possession by the males of tufted antennae and a more elongated shape. As a general rule the larvae of naked-winged species of Ceratopogon are aquatic, those of hairy-winged species terrestrial. The eggs of aquatic species are laid in floating alga;, in star-shaped clusters containing from one hundred to one hundred and fifty. The larva; of these species are whitish worm-like creatures, with long narrow heads ; they live in the masses of Confervse floating on the surface of stagnant pools and ditches, and progress with a serpentine motion. The larvae of the hair\'-winged 14 s|jccies live under the damp bark of dead trees, in weeping spots on tree triinii-m= Caliier (Metz: 1901.), p. 143) for Uie group of species which includes Ceratopogon varim, Winn., & C. puluaris, l.iiui. The aulhor in ipiestion also introduced three other genera at the expense of the nld genus Ccratopoi^oii, which, owing to the large ninnber of species comprised in il, w.is in urgent need of division. For the purposes of the present wurk, however, it has licen thought unneces.sary to change the nomenclature adopted in Verrall's ' List,' 2nd 1>1. (1901). IS Geratopogon pulicaris, Linn. Plate I, fig. 2. In certain localities in England in the latter part of April and beginning of May, 1904, this midge was especiall)' abundant, and much inconvenience was caused by its bites. A correspondent writing from Romford, Essex, on April 28th, with reference to the multitudes of Ceratopogoii pulicaris w ith which the town was then afflicted, said : — " They swarm in countless m_\-riads, and their bite is very virulent, to me worse than a bee-sting, or the bite of any gnat. I have never seen them before in anything like the quantities, neither have I known the effects to be so severe and lasting. No doubt the hot sun and damp soil have brought them out, as in the tundras." Writing again on May ist, the same correspondent said : — " The insects were in such large numbers that b\- just turning a killing- bottle through the air I soon got a pill box full. Many of my Ci-iidopogon /u/iuzris, Linn. ( 9 ), in resting position ( ;•; 1 2). neighbours had lumps on their necks, and their faces like measles, while some of the workmen ' struck.' " In many other localities near London, such as Epping Forest, Harrow, and the suburb of Stoke Newington, this pest was also very prevalent at the same time, and in \6 consequence of their attacks, people found it impossible to remain in gardens after 5 p.m. Ceratopogon piilicaris measures 2 mm. in length, and is therefore considerably larger than C. varius; it abounds throughout Europe, and can easily be recognised b}' the marking of the wings, which when closed appear to have transverse bands. Note. Tlie Harvest Bug {Lepltis atiltimnalis, Shaw), x lOO. (.Vftcr Mcyiiin.) The irritating swellings caused by Harvest Bugs are occasionally mistaken for the biles of midges or gnats. The Harvest "Bug" (I.efliis aulumnalis, Shaw) is really a Mile, a minute .\carus, — the six-legged larva of a s]iecies of Tromhidiiim ; it is (xissiblo that larv;v belonging to more than one species are included under the same name. The annoyance is caused by these >oung forms hunoiviin; into the sUin, generally about the ankles and knees. Midges and gnats more usually attack the exposed parts of the bod), although the females of both fimilies readily bite through ihin clothing. 17 Family CULICID^. Gnats or Mosquitoes. In view of the large amount of popular misconception that appears still to exist with reference to the meaning of the terms " gnat " and " mosquito," it ma}' be worth while once again to emphasise the fact that, proper!)- used, the\- apply to any species of the family Culicidre, so that, if we prefer to employ a word of foreign origin rather than the Old English gnat, our British species of Anopheles, Culex, etc., are as much entitled to be called niosqnitoes as are tropical species belonging to the same genera, from many of which they would be indistinguishable to the untrained observer. Including certain non-blood-sucking forms belonging to the genera Corethra, Mochlonyx, and A'luies, the species of mosquitoes now recognised as British are twenty-two in number. Many harmless midges belonging to the genera Chirononius and Tanypus resemble gnats more or less closely in outward appearance, but, apart from other structural characters, may be distinguished hy the absence of the long, piercing proboscis, as also by the habit of holding up the front legs when at rest, whereas a gnat in the same position elevates its hind legs. In British, as in all mosquitoes with possibly one or two exceptions, the blood-sucking habit is confined to the female se.x. The males may be distinguished by their plumed antennae, and in the genera Theobaldia, Culex, and Grabhaniia by their elongate palpi. In Anopheles the palpi are as long as the proboscis in both sexes, but in the male their tips are thickened, bent outwards, and somewhat plumose. The preliminary stages of all mosquitoes are passed in water. The wriggling larvae and comma-shaped pupae of the common gnat {Culex pipiens, Linn. — Plate 8), v,'hich are familiar objects in cisterns and rain-water butts in summer, may be taken as types of those of the species belonging to the genera Theobaldia, Culex, and Grabhamia. In the case of the latter genus the eggs are usually laid singly. The eggs of the species belonging to the two former genera somewhat B i8 resemble tiny " Indian clubs " in shape, and are deposited on the sur- face of the water, arranged vertically in compact masses, or "rafts," each containing from 200 to 300 eggs. The eggs of the species of A/iop/teles, on the other hand, are boat-shaped, and are not attached to one another, but float freely on the surface of the water in clusters of from two or three to as many as 100. The larvar of the Culicinre are distinguished by the possession of a posterior dorsal breathing tube, or respiratory siphon, which is absent in the Anophelinac. W'hen taking in air, the former suspend themselves at an angle from the surface film by the extremity of the respiratory siphon, but the larvae of the latter lie perfectly horizontal. The food of mosquito larvne consists of algae and minute organisms, both animal and vegetable ; in captivit}' they sometimes display cannibal propensities. In addition to the species illustrated in the plates, the following blood-sucking mosquitoes are also found in the British Islands : — Culex morsitans, Theob., lateralis, Mg., ornatus, Mg., divcrsus, Theob., nigripcs, VAI. var. sylvcr, Theob., Jiigritulus, Ztt., Intescens, Fabr. ; Grabhamia pulchripalpis, Rond. ; and Taiiiorhyfichus richardii, Fie. Genus ANOPHELES, Meigen. Anopheles nigripes, Stseg. Plate 2. Specimens of this species in the Museum collection are from various localities between and including CoIw\-n Bay, Carnarvonshire, N. Wales, and Penzance, Cornwall : the species is on the wing from June to September. According to Theobald (' Monograph of the Culicidai,' Vol. I., p. 202) it also occurs in Scotland, and what appears to be A. nigripes was recorded (without a specific name) from the North of Ireland by A. H. Haliday in 1828 (' Zool. Journal,' III., 1828, p. 501). Theobald {loc. cit.) writes of this species : — " It bites very viciously, 19 and the bite is somewhat annoying. It usually occurs on the wing at dusk I have taken this mosquito in the daytime by beating dense bushes where it seems to pass the day in North Wales." The same writer states that A. nigripes "does not appear to come intloors," but the Museum possesses a female which bit and sucked blood, and was taken by Mr. F. W. Terry at Merton, Surrey, on June 6th, 1899, in a bedroom at night. According to Nuttall, Cobbett, and Strangeways- Pigg ('The Journal of Hygiene,' Vol. I., 1901, p. 12), in the British Islands Anopheles nigripes is much more rare than either of the other two species of the genus, although there is no difference in the distribution of any of them. Out of 156 British specimens of Anopheles from various localities, no fewer than 123 were Spotted Gnats [A. maculipennis, — Plate 4), 27 belonged to A. bifurcatus (Plate 3), and only six to the present species. The geographical range of A. nigripes is said to include Northern Europe and North America. Anopheles bifurcatus, Linn. Plate 3. This species, which occurs throughout Europe.from Lapland to Italy and the Mediterranean, is probably generally distributed in the British Islands, since it was recorded by Haliday from the north of Ireland, and the localities of the specimens in the Museum include Torphins, Aberdeenshire, N.B., and Penzance, Cornwall. According to Theobald [op. cit., p. 198) this mosquito makes its appearance in England in April and May ; a male and female were taken at Penzance by Mr. F. VV. Terry on July 17th, 1901. Theobald writes that the female of .^. bifurcatus attacks human beings, and is a ver\- persistent blood-sucker ; " it is much fiercer than the more common A. maculi- pennis" or Spotted Gnat (Plate 4). The same author adds that he has found the species chiefly in the neighbourhood of woods, and that malarial parasites are known to develop in it in Italy. 20 Anopheles maculipennis, Mg. The Spotted Gnat. Plate 4. Like the foregoing species, this is one of the mosquitoes chiefly concerned in the dissemination of malaria in Itah' at the present da_\-. It is widely distributed in Great Britain, and is verj- common in many places. In Ireland it was recorded by Haliday in 1827 (' Zool. Journal,' Vol. III. (1828), p. 501) as occurring "in profusion, in the neighbourhood of Belfast, throughout the summer and autumn." In England, according to Theobald {pp. cit. p. 193), the time of appear- ance of this species is "from March to May, and again from June to December." The same writer adds that : — " The majority appear in July and August. Females only occur early in the year." He also states that specimens " may be found in the daytime settled inside outhouses and privies." British females of A. maculipennis would appear sometimes to be less blood-thirst}- tiian those of either of the foregoing species, and Theobald's experience has been that botii sexes subsist entirely on vegetable food. If this is the case it would suggest that a change must have taken place in the feeding-habits of British females of this species, since the time when ague (malaria) was prevalent in this country. Nevertheless there can be no doubt that on occasion females of A. maculipennis in the British Islands suck blood at the present time. Thus, in their paper on ' The Geo- graphical Distribution of Anopheles in Relation to the Former Dis- tribution of Ague in England,' published in January, I90i,it is stated by Nuttall, Cobbett, and Strangeways-Pigg (Joe. cit., p. 10) on the basis of investigations made in the previous year : — " That the English Anopheles maculipenuis is just as fond of blood as its continental con- freres has been amply proved by experiment during July and August." Again, a correspondent who wrote from Langport, Somerset, on August 1 6th, 1905, and forwarded for identification specimens of this species and Tlieobaldia annulata, Schrk. (Plate 5), complained that : — " Since residing in Langport, which is on the level of Sedge- 21 moor, we have been troubled every summer with the enchDsed gnats, which, coming into the bedrooms, assail the sleepers to such an extent that we have to adopt mosquito curtains." Anopheles maculipenuis, which occurs throughout Europe and has been met with in Palestine, is also widely distributed in Canada and the United States. Before bringing to a close these brief notes on the British represen- tatives of the malaria-bearing genus Anoplieles, it may be interesting to reproduce the following " Conclusions " from the paper by Messrs. Nuttall, Cobbett, and Strangeways-Pigg already referred to {loc. at. pp. 43-44). " I. The disappearance of ague from Great Britain does not depend upon the extinction of mosquitoes capable of harbouring the parasites of malaria. " 2. Three species of Anopheles {A. iiiacnlifenins,A. bifiircatus, A. nigripes) are to be found in Great Britain in all districts which were formerly malarious, but also in places con- cerning which there is no record of the former prevalence of ague. The Anopheles to-day are most numerous in low-l\-ing land containing many ditches, ponds, and slowly-flowing water, suitable for their habitat, and corresponding to the dis- tricts where ague was formerly prevalent. " 4. Since the disappearance of ague does not depend upon the extinction of Anopheles it is probably due to several causes operating together : " {a) A reduction in the number of these insects conse- quent upon drainage of the land, this being in accord with all the older authors, who attributed the disappearance of ague largely to this cause. " {b) Reduction of the population in infected districts as the result of emigration about the time when ague dis- 22 appeared from England. This would naturally reduce the number of infected individuals and thus lessen the chance of the Anopheles becoming infected. " ( G. F. Haiiipson, Bt.) ; a female from the same locality, presented by the Entomological Club, in 1844 ; and a second female, taken at Marcha, near Yakutsk, Siberia, on June 7th, 1900. According to Brauer, Th. borcalis ranges from Lapland and Sweden to the Austrian Alps. Therioplectes montanus, Mg. Plate 14. In British specimens of this species there is a considerable difference in appearance between the two sexes, due partly to the male abdomen being more pointed at the tip (as is also the case in other species), and partly to the contrast of colours in the abdomen being much sharper in the male than in the female. Of three males of Th. montanus in the Museum collection, from Loo Bridge, Co. Kerr_\-, Ireland, the smallest is 12, the largest 13^ mm. in length ; the length of seventeen Scotch and Irish females varies from 12 to 14^^ mm. Continental specimens are larger, and may attain a length of 16 and 17 mm. in the case of the male and female respectively. The area of enlarged facets in the upper portion of the eyes of the male is not sharply distinguished from the remainder of the eye-surface. Brauer {/oc. cit., pp. 144- 145) describes the coloration of the eyes of the male as " green, with three purple bands and red lower margin bordering the face"; while, with reference to the female he writes : " E\'es emerald-green, with three linear carmine-red bands, the middle one of which often does not reach the hinder margin of the eye ; upper and lower margin emerald-green." So far as regards the British fauna, TIi. montanus would appear to be essentially a Scotch and Irish species, since the Museum collection includes no specimens from England or Wales. Colonel Yerbury's note runs : " Very common in Ireland, at Loo Bridge and other places in County Kerry ; common, too, in Scotland, where in July it succeeds Th. luridns in the sand-hills ; it also occurs, among other localities, on the lower slopes of the Cairngorms." The Scotch specimens in the Museum are from Invershin, Sutherland; Nairn; Brodie, Elgin ; Nethy Bridge, Inverness-shire ; and Rannoch, Perth- 40 shire ; all taken by Colonel Yerbury between July 3rd and 26th inclusive. Vwm Ireland there are examples from Leenane, Co. Galway, and Louyh Conn, Co. Mayo, July 14th and 27th (E. E. Austen) ; and from Loo Bridge, Co. Kerry, July 6th-8th (ZiV?^/.-^!?/;;//^/ Yerbury). The Continental series is from various localities from Norway to Rhenish Prussia. Ihe range of the species as given b\- Brauer, in addition to Germany and Austria, includes Sweden, Russian Lapland, South Russia, and Eastern Siberia. Therioplectes luridus, Iln. Plate 15. This handsome species resembles the foregoing ( 77/. viontanus) in size, while (as ma}- be seen from a comparison of Plates 14 and 15) the general arrangement of the light and dark markings in the abdomen is similar to that presented b\- females of Th. inontanns, in which the lateral ochraceous patches are well developed. The colours in the abdomen of Th. luridus, however, are much richer ; the black area is deeper in tone and more shining, while the lateral patches are chestnut instead of ochraceous. The predominance of black makes this a distinctly darker species than the foregoing. In both sexes of Th. luridus the hairy covering of the eyes is longer and darker than in Th. nioutanus (dark brown instead of yellowish brown or yellowish). Brauer [loc. cit., p. 148) describes the eyes of the male as "green, with three pur])le bands and red margin next the face," and those of the female as " green, \\ith three purple bands." The length of two males of Tli. luridus in the Museum collection, from Brodie, Elgin, N.B., June 9th and lOth, 1905 {Lieut.-Colonel Yerbury), is I2J and 13 J mm. respectively; .sexenteen Scotch females vary in length from iii to 14^ mm. The dimensions of Continental specimens arc much the same, though a male from Norwaj- measures as much as 14 mm. in length. A long series of this species was taken by Colonel Yerbury at Brodie, from June 5th to June loth, and at Nethy Bridge, Inverness- shire, N.B., from June 12th to July 1st, 1905. It will be observed 41 that the female specimen ilkistratcd in Plate 15, which was taken by Colonel Yerbury at Aviemore, Inverness-shire, on June 5th, 1904, has a small appendix to the upper branch of the third vein in each winL,s and traces of a similar appendix are to be seen in some of the other specimens in the Museum. In the British Islands Therioplectes luridus would appear to be a northern species, and as yet the Museum possesses no specimens from either England, Wales, or Ireland. Colonel Yerbury writes : — " In Scotland this is the earliest <>f the Tabanida;. In May 1905, it was met with in numbers near Nairn, when both sexes were found sitting on a sandy road leading to Mairston Sand Hills. A single female was taken at Aviemore on June 5th, 1904. Probably all the Tabanida; seen by me in Scotland at this time of the year belonged to this species." The Continental specimens of this species in the Museum collection are all from Norway; additional localities given by Brauer are Swedish-Lapland, Sweden, Poland, Silesia, and Bohemia. Therioplectes tropicus, Pz. {tiec Mg.). (Form bisignatns, Jaenn.) Plate 16. In its typical form this species has an ochraceous or ochraceous- buff patch on each side of the abdomen extending from the posterior angles of the first to the posterior margin of the third or anterior border of the fourth segment, leaving a broad median black stripe one-third of the abdomen in width. Two males in the possession of the Museum from Oxshott, Surre}', June 9th, 1895 {Lieiit.-Coloncl Yerbury and IF. R. Ogilvie Grant), and Chattenden Roughs, Kent, July I2th, 1902 {H. W. Aiidreivs), respectively are of this character, but the whole of the British females in the Museum series [15] are of the melanochroic form bisignatns, of which a specimen is illustrated in Plate 16, which accordingly would appear to be the common British form of the female of this species. As a further proof of this conclusion it maybe mentioned that at Oxshott on June 9th, 1S95, 42 Colonel Yerbiirj' and Mr. W. R Ogilvic Grant took, in addition tn the normal male already mentioned, three females of the bisignatits form. In many of the females in the Museum collection there is no trace of the russet markings on the sides of the second abdominal segment seen in the specimen shown in the plate, but the abdomen appears wholly black, with, however, a longitudinal row of whitish markings on each side of the median series of white triangles. The resemblance between the form bisiguaius and TheriopUctcs iiikans, Mg., has already been alluded to in the notes on the latter species (see page 7,y). The two males of T/i. tropicus referred to above are 145 mm. in length, with a wing-expanse of 28 mm. ; the length of the females varies from i4to iSjmm. According to Brauer {loc.cit., pp. 146-147) the eyes in this species are green with three purple bands ; in the male the lower margin is green and unbanded. The Museum pos- sesses no specimens of this species from Wales, Scotland, or Ireland, but in England at any rate Tli. tropicus appears to be among the more common of the larger horse-flies. The dates of capture of the females in the Museum series range from Ma\' i6th to July 12th inclu- sive, and the localities are Brinklow, Warwickshire {E. E. Austen); Berkhamsted, Herts ( W. R. 0. Grant) ; Feldcn, Boxmoor, Herts {A. Piffard); Colchester, Essex ((/'. //. Haruood) ; Oxshott, Surre\- ( //'. R. 0. Grant and Lieut.-Colonel Yerhurr) ; and New Forest, Hants [Lieut.-Culonel Yerbury and C. 0. Watcrhouse). In the last-mentioned locality Colonel Yerbury notes that bisignatus is the common form of the S[jecies. Continental sjjecimens of Tli. tropicus in the Museum collection are from Siberia, Norway and Russia (typical form), and fmm Rhenish Prussia (form bisignatus). Additional Continental localities given by Brauer are Sweden, Germany and Austria for the t\-pical form, and France, Silesia and Asiatic Russia for the form bisignatus, which was originally described from a specimen from the neighbour- hood of Paris. 43 Therioplectes solstitialis, Schin., Brauer (? Mg). Plate 17. In this species, which is the most brightly coloured of the larger British Tabanida?, the two sexes are alike in coloration, though the black median dorsal stripe on the abdomen is usually narrower and more distinctl_\- defined in the male. Of eight British males in the Museum collection the smallest is 14I, the largest 16^ mm. in length, while twenty females vary in length from 14^ to 17 mm. The eyes of the male according to Brauer (/^^. cit., p. 150), are "dark green, with a strong purple sheen above, with two purple bands on the lower third, and with the rudiment of a similar band on the edge of the larger facets " ; those of the female are described as " bright green, with a coppery sheen, or bluish green, with three narrow- purple bands, which often have a )'eIlow edging." The dates of capture of the Museum series of TIi. solstitialis range from June 13th to July 22nd inclusive. The localities are, in Scotland : Nethy Bridge and Aviemore, Inverness-shire ; Nairn ; Brodie, Elgin ; and Rannoch, Perthshire {Lieut.-Colonel Yerbtny) ; Taynuilt, Argyll- shire {A. Beaumont) ; and Goatfell, Arran {Sir G. F. Hatiipson, Bt.). In Wales : Barmouth, Merionethshire {Lieut.-Colonel Yerbuiy). And in England : Tarrington, Herefordshire ; Lyndhurst, New Forest, and Ringwood, Hants {Lieut.-Colonel Ycrbiiiy)-. Beaulieu, Hants {Miss Gertrude Ricardo) ; Avon and VValkham Valleys, S. Devon {Lieut.-Colonel Yerbuiy); and near Bude, Cornwall (.5. G. Rye). In the Museum general collection there are specimens from Norway, and the localities given by Brauer show that the species occurs south- wards as far as Hungary and the Tjrol, and eastwards on the Amur river in Russian Asia. Colonel Yerbury writes that in Great Britain Th. solstitialis is " very common and general!}' distributed. The males are frequently seen hovering over roads through woods, and the habit seems to be confined to this species. Although not painful, the bite of the female is very severe, and draws blood more often than that of any other species." 44 Gi:.\us ATYLOTUS, Osten Sacken. Atylotus fulvus, Mg. Plate 1 8. The general ochreous colour of the bod}- will .ser\e to distinguish this species, which is one of the rarer of our British horse-flies. Rubbed specimens, however, look darker owing to the disappearance of the short silky golden hairs, which co\ er the body and produce the characteristic hue, and in the specimen figured in the plate these hairs are unfortunately wanting on the abdomen. The only British specimens of A . /n/vus that the IMuseum possesses are a male, from Lyndhurst, New Forest. Hants, June 24th, 1897, and five females, from the same locality and L)-ndhurst Road, June 29th and Jul)' 8th, 1897 {Liciit. -Colonel Yerhury) ; Beau- lieu, Hants, July 15th, 1898 {Miss Gertrude Ricardo) ; and Kenmare, Co. Kerry, Ireland, June 30th, 1901 {Lieut.- Colonel Verditrj). The length of the male is 14' mm. ; that of the five females varies from 14I: to iSj mm. The eyes of the male are usually without bands; those of the female are described by Brauer {loc. cit., p. 170J as " pale olive-green, with an oblique fine dark line and shot with several almost black round spots." In the male of this as of the following species an area in the upper half of the eye, running from the inner nearl)- to the outer margin, is composed of much larger facets than the remainder. Writing of A. fulviis Colonel Yerbur\- sa\s that it is "a rare species," and that he has met with it " onl_\- in the New Forest, and at Glengariff and Kenmare in Ireland." The Continental series of this species in the Museum collection includes examples from Hungary,Switzerland, and Spain. According to Brauer it is generally distributed throughout Central and Southern Europe, and is also found in Scandinavia, Russia, and Asia Minor. 45 Atylotus rusticus, Fabr. In the British Islands this species is even more rare than the foregoing, from which it may be distinguished by the greyer tint of the short hair covering the bod)'. The dimensions are similar to those of A.fidvus. The eyes of the male sometimes have a purplish transverse line at the junction of the large and small facets ; similarl)' those of the female are either unbanded or in some cases have a single narrow band. The only modern British example of this species in the Museum is a male from North-east Essex ( W. H. Harwood), of which the date of capture is unfortunately unknown ; but a male and female without locality labels are contained in the old Stevensian collection. The general collection of Diptera includes specimens from France, Hungary, and Algeria. The localities given b\- Brauer {loc. cit., p. 169) show that the species is distributed throughout Central and Southern Europe. Genus TABANUS, Linnaeus. Tabanus bovinus, Lw. (.Schiner pro parte) Plate 19. This and the following species, Tabanus sudettais, Zlr. (Plate 20) are the bulkiest of all British Diptera, and on the whole T. sudeticus is slightly the larger of the two. Although as a rule specimens of the latter species are distinctly darker than those of T. bovinus, the females are often difficult to distinguish, and it is by no means easy to give thoroughly satisfactory characters for their separation. The males of the two species, on the other hand, can readily be distinguished owing to the fact that while the facets in the upper half of the e\-e of T. 46 bovinus are not noticeabh- larger than those in the lower, the facets in the upper two-thirds of the eye of the male T. sudeiiciis are, with the exception of those on the hinrl margin, at least four times the size of the rest. In both species the eyes are devoid of bands, and, according to Brauer {loc. cit., pp. 184, 185), in the living insect, while those of the male of T. bovinus are entirely green, the eyes of the male T. siidetiais are " blackish, with a copper)- sheen, the larger facets greyish, the smaller ones more reddish." In the case of the females the colour of the eyes is given b}- Brauer [loc. cit., p. 136) as "emerald green" in T. bovinus, and as " alwa)-s blackish-brown, with a coppery sheen " in T. sudeticHS. In both sexes the pale hind margins- of the abdominal segments are usually more distincth- marked off from the ground colour in T. sudeticus than in T. bovinus. The British series of Tabanus bovinus in the possession of the Museum includes two males (both of which arc from the Waller Clifton collection, and unfortunately without either localities or dates), and nine females, all from the southern counties ; the following are the localities and dates of the female specimens : — Oxshott, Surrey, June i6th, 1895, (IF. R. Ogilvie Grant); Farnham, Surrey, Julj' 13th, 1899, — "on window of Sub Post Office" (yj. Rawlins) ; Froyle, Hants, July 6th, 1893 {IV. R. Ogilvie Grant) ; L}-ndhurst, New Forest, Hants, June 30th, 1894 (Lieut.-Coloncl Yerburj'), July 2ist, 1890 (F. IV. Fro/iazvk), and August, 1893 (Z. C. C/mwner) ; Ringwood, Hants, June 29th, 1894 {Lieut. -Colonel Yerbury); and Ivybridge, S. Devon, July 26th, 1889 {Lieut. -Colonel 1 'erbury). The two males are respectively 20 and 2 1 \ mm. in length, and their wing-expanse is 371 mm. in the one case and 39 mm. in the other. The smallest British female in the Museum series is 21 j mm. in length, the largest 23I mm. (wing-expanse 47 mm.). In addition to British specimens of T. bovinus, the Museum possesses examples from the South of France, Hungar\-, and Poli.sh Ukraine. Additional localities given by Brauer show that the species is found from Sweden to Italy, and eastwards to Siberia and the Amur. Of the habits of this species Brauer writes {loc. cit., \x 187): — " The females swarm round horses, cattle, and deer. The males hover in the air in clearings in woods, and above somewhat elevated places 47 in meadows, but not on mountain tops ; the}' do this especiall)- on ■sulti-}', thundery days, in the sun after downpours of rain, or early in the morning." Tabanus sudeticus, Zlr. Plate 20. The British specimens of this fine species in the Museum collec- tion consist of one male (length 2o| mm.) and thirteen females ; the length of the latter ranges from 2oi to 24I mm. ; the wing-expanse of the largest female is 48 mm. In view of the particulars as to this species already given (see T. boviiius), it is now only necessar_\- to refer to the localities and dates of our specimens. Brauer {/oc. cit., p. 185) states that in Austria T. sudeticus ison the wing much laterin the }'ear than T. boviniis, and that while the latter occurs in Ma\- and until the middle of June, the former is met with at the end of June and throughout July and August. In the British Islands, however, the time of flight of the two species would seem to be pretty much the same. The localities and dates of the British specimens of T. sitdcticns in the Museum collection are as follows: — Brodie, Elgin, N.H., August 2nd, 1905 (^Lieut-Colonel Yerbury) ; Nethy Bridge, Inverness- shire, N.B., July 8th and 9th, 1905 {Lieut-Colonel Yerbury) ; Drimmin, Sound of Mull, Argyllshire, N.B., 1904 {Miss Henrietta Brozvn) ; Birnam, Perthshire, N.B., August 25th, 1894 {H. S. Barr); Goat Fell, Arran, N.B., June 20th, 1893 {Sir G. F. Hatnpson, Bt.) ; Felden, Boxmoor, Herts, July 7th, 1893 {A. Pijfard) ; Budshead Wood, S. Devon, July ist, 1889 {$), and Walkham Valley, S. Devon, July 31st, 1896 {Lieut-Colonel Yerbury'); Kenmare, Co. Kerr\-, Ireland, June 28th, and Jul}' 7th and loth, 1901 {Lieut-Colonel Yerbury); and Glencar, Co. Kerry, August i6th, igoi {Lieut.-Colonel Yerbury). Colonel Yerbur)' writes : — " Tabanus sudeticus, Zlr., was the commonest horse-fly at Kenmare in July, 1901 ; in Scotland it seems to be rather an uncommon species. T. sudeticus d^nd T. bovinus 4!S includes Central and Southern Europe. The Museum possesses specimens from Brittany the South of France, Spain, and the Tyrol. 53 Genus CHRYSOPS, Meigen. Chrysops csecutiens, Linn. Plate 26. The figures in the plate illustrate the striking sexual difference in the coloration and marking of the abdomen, which, though also seen in the case of Chrysops qiiadrata and relicta, is much more pronounced in the present species. It should be noted, however, that on the ventral surface of the abdomen of the male C. avcutiens there is a yellow patch on each side, which frequently extends on to the upper surface and forms a more or less conspicuous ochraceous fleck on each side of the second segment. In life the eyes of this as of the other species of the genus are extremely beautiful, even when com- pared with those of other Tabanida;, which as a family are distin- guished for the beauty of their eyes ; the ground-colour is golden or, reddish-green, and is marked with purple spots and lines. Chrysops ccecutiens has been taken by Colonel Yerbury at Torcross S. Devon, as early as May 24th, and the Museum series of specimens shows that it is on the wing at any rate until the end of the first week in August. The dates and localities of the specimens are as follows : — Nairn, N.B., July 17th, 1904 {Licut.-Coloncl Ycrbiiry) ; Oundle, North- ants, July i6th, 1905 {Hon. N. C. Rothschild); Rugby, Warwickshire, July 3rd, 1890, July loth, 1892 {E. E. Austen); Felden, Boxmoor, Herts, July 24th, 1893 {A. Piffard) ; Bearsted, Kent, July loth, 1896 {E. E. Green); Fawkham, Kent, July 7th, 1895 {W. E. de Winton) ; Tilgate Forest, Sussex, August 3rd, 1890 {E. E. Austen); Woolmer Forest, Hants, August 7th, 1892 ( W. R. Ogilvie Grant) ; Lyndhurst and Lyndhurst Road, New Forest, Hants, June 25th to July 12th, 1894 {^Lieut-Colonel Yerbury); various localities in S. Devon, May 24th to July 28th {Lieut.-ColoHcl Yerbury) ; Porthcawl, Glamorganshire, S. Wales, June 17th and iSth, 1903 {Licut.-Coloncl Yerbury). 54 111 England, on the whole, this is probably the commonest species of its genus, although in some localities its place appears to be taken by Chrysops relicta. Colonel Yerbury writes that " the genus Chrysops does not seem to be plentiful in Scotland " ; and he further adds that " Chrysops and Fhciiintopota are silent or almost so in their approach; Tabaniis, on the other hand, announces its arrival with a more or less loud hum." At Brockenhurst, in the New Forest, on July 14th, 1894, Colonel Yerbury captured a female of Macliiiniis atricapillus. Fin. (a small Robber-fi\-), feeding on a male of the present species. The geographical range of Chrysops acciitiois extends throughout Europe to Siberia ; the Continental series in the Museum includes specimens from France, Germany, Bohemia and Corsica. Chrysops quadrata, Mg. Plate 27. In the male of this species the basal half of the abdomen shows a considerable amount of \ellow at the sides, though the median quadrate black spot on the second segment, which is a continuation of the black area on the first, is very much larger than in the female, and nearly reaches the hind margin. As in the female, the hinder portion of the third segment, and sometimes that of the fourth as well, is conspicuouslj' )-ellow. The median black spot on the second abdominal segment of the female is variable in shape as well as in size, being sometimes nearly square and sometimes more or less dis- tinctly cordate. In the specimen illustrated it is connected with the blotch on the first segment, but more frequentl)' it is separate. Ne.Kt to Chrysops scpidcliralis, Fabr., C. quadrata is less often met w ilh than any other of the British species of the genus. Colonel Yerbur)' writes that it is " as a rule rare, but is the common form in Denny Wait in the New Forest." The Museum series at present consists of one male and eight females, from the following localities : — Guestling, Hastings, Sussex, 1892 {Rro. E. N.Bloovifield); Lyndhurst and L\ndhurst Road, New Forest, Hants, July 3rd, 4th, and 21st; 55 August 14th, and September ist, i2>g^ {Liciit.-Colonel Ycrbuty); Holne, Dartmoor, S. Devon, July 6th, 1896 {Lieut. -Colonel Yerbiiiy). Chiysops quadrata occurs on the Continent in Central and Southern Europe ; the general collection includes specimens from France, German}', Hungar}', and Corsica. Chrysops relicta, Mg. Plate 28. The width and shape of the black blotches on the second abdo- minal segment, as well as the sharpl)- defined pale triangles and hind margins on the following segments afford a ready means for the dis- tinction of the female of this species from that of C. ciccutiens. In the specimen illustrated in the plate the blotches on the second seg- ment are somewhat obscured by the wings, which are in the resting position. The markings of the male abdomen are similar to those of the female, but the sides of the basal portion are more tawnj', and the pale triangles are much less distinct. The Museum series of British specimens of this species, which as Colonel Yerbury remarks, is " common and generall)- distributed," is a fairly long one, and shows that it is on the wing from the latter end of May until at any rate the third week in August. The localities and dates of the specimens, which, unless otherwise stated, were taken and presented by Lieut.-Colonel Yerbury, arc as follows : — Nairn, N.B., July t/th, 1904 ; Aviemore, Inverness-shire, N.B., July 7th and 9th, 1899, and August iSth, 1898; Rannoch, Perthshire, N.B., July nth, 1898; Lyndhurst, New Forest, Hants, July 4th, 1894; Brockenhurst, New Forest, August 17th, 1893 ( fF. R. Ogilvie Grant) ; Torcross, S. Devon, May 24th to 26th, 1893 ; Porthcawl, Glamorganshire, S. Wales, June 25th, 1903 ; Leenane, Co. Galway, Ireland, July 14th, 1892 (E. E. Austeu) ; Kenmare, Loo Bridge, and Parknasilla, Co. Kerry, Ireland, July 2nd to 15th, 1901. The range of this species on the Continent includes Northern and Central Europe ; the Continental series of C. relicta in the possession 56 of the Museum, although at present \ery limited, includes specimens from such widely distant localities as the North Cape, Norwa)', and the South of France. Chrysops sepulcralis, Fabr. This species was not known to be British until two males were taken on Studland Heath, nearSvvanage, Dorset, on August 3rd, 1895, by Captain Savile Reid, by whom they were presented to the British Museum (Natural History). No further specimens of C. sepulcralis have since been received by the Museum, but a female was taken on Parle}' Common, near Ringwood, Hants, on August 8th, 1904, by Mr. G. H. Verrall. Chrysops sepulcralis, which, in the British Islands, consequently appears to be decidedly rare and local, is a small species ; the two males referred to above are 8^ mm. in length, while a female from German)' measures only ]\ mm. In this species the body is entirely black in both sexes, the outer margin of the dark transverse band across the wing is concave instead of, anteriorly at least, convex, and the face (except immediatel}' beneath the base of the antennje) is wholly shining, the facial and jowl-tubercles being confluent. The geographical range of Chrysops sepulcralis includes Scandinavia, Gcrman\', and Russia. 57 Family MUSCID/E. The three British blood-sucking species belonging to this Fam'iy are all nearly allied to the Common House-fly {Miisca domestica, Linn.), but derive an even greater interest from their close relationship to the African Tsetse-flies (Genus Glossina), one species of which, Glossiiia palpalis, Rob.-Desv., is now widely known as the disseminator of the parasite which is the cause of the dread disease called sleeping sickness. In the Muscida;, which, in the widest sense of the term are perhaps the largest of all the families of Diptera, the blood-sucking habit is highly exceptional and is confined to a very few genera and species, all of which in appearance present a general resemblance to the Common House-fly. In cases in which the blood-sucking habit occurs, it appears to be common to both sexes. Blood-sucking Muscidae, with the exception op the Tsctsc-Jlics, breed in dung, depositing eggs from which are developed white maggots of the type of those of the Common Blow-fly {Calliphora eiythrocephala, Mg.). According to Riley and Howard, Lyperosia irritaiis, Linn. {Hceinatobia scrntta, Rob.-Desv.), (Plate 30, fig. 2), oviposits on fresh cow-dung, and its eggs are irregularly oval in shape, flattened on one side, and from r25 to 1-37 mm. in length, by 0'34 to 0"4i mm. in width. The newly-hatched larvae descend into the dung, and eventually when full-grown attain a length of 7 mm. Pupation takes place in the ground beneath, at a depth of from half to three- quarters of an inch. The pujiarium is of the normal Muscid type, dark-brown in colour, barrel-shaped, and from 4 to 4'5 mm. in length by 2 to 2"5 mm. in width. Stoiiio.xys calcitnms, Linn., breeds in horse-droppings, and its larva; are very similar to those of the Common House-fly, which also breeds in horse-dung. 58 Genus STOMOXYS, Geoffroy. Stomoxys calcitrans, Linn. Plate 29. The similarit}- in size between this species and the House-fly {Mtisca domestica, Linn.) sometimes causes Stomoxj's to be mistaken for the latter, with the result that the House-fly is occasionally supposed to be capable of biting. Apart from points of difference afforded b)- markings, however, Stomoxys, not to mention other struc- tural differences, can always be recognised b}- the little black, rigid piercing proboscis, which, as shown in the plate, when not in use projects horizontally in front of the head, whereas the fleshy, non- biting proboscis of the House-fly is normally carried drawn up into a cavity on the under side. The sexes of the present species can be distinguished by the front (space between the eyes) in the male being scarcely more than half the width of that in the female. Stoinoxfs calcitrans, which is the only European species of its genus, and, like H(.ematobia stiinu/. calcitrans, and the eyes in the male are 6o much closer together, being only narrowly separated. The palpi, which in 5. inlcilni)isa.re exceedingly slender and short, and cannot be seen when tiie insect is viewed from above, in the present species are prominent and expanded at the tips, and, though still distinctly shorter than the proboscis, are apparent!}' capable of forming a partial sheath for that organ. The localities of the Museum series of specimens of this common species include the Northern Sutor, Cromarty, N.B., and Dartmoor, S. Devon ; in addition to \arious places in the midland and southern counties of England, there are also specimens from Barmouth, N. Wales, and Kenmare, Co. Kerry, Ireland {^Lieiit. -Colonel Yerbiiiy). The dates of capture range from May 5th to September 6th. For Colonel Yerbury's notes, see the previous species. The Museum unfortunately possesses no specimens of HiEinatobia sthnulatis from localities outside the British Islands, but it is probable that on the Continent it is as widely distributed as 6". calcitraus, although, so far as the writer is aware, it has not yet been recorded from any locality outside Europe. Zetterstedt states that it occurs throughout Scandinavia, but in Austria, according to Schiner, it is somewhat rare. Genus LYPEROSIA, Rondani. Lyperosia irritans, Linn. Plate 30, fig. 2. In this species, whicii is b_\- far the smallest of our native blood- sucking Muscid.x-, the female measuring only from 4^ to 5 mm. in length, the palpi, as in the Tsetse-flies (GlossiiKi) are flattened from side to side and form a complete sheath for the proboscis, which they equal in length. Lyperosia irritans does not appear to attack human beings, but is a pest of cattle, on the backs of which it is found, show ing, according to Zetterstedt, a preference for black animals ; this latter 6i trait is in accordance with the well-known predilection of other blood- sucking Diptera, such as Anopheles and HcEiiiatopota, for resting upon dark surfaces. The localities and dates of the Museum series of specimens are as follows : — Felden, Boxmoor, Herts, September 5th, 189s (^. Piffard) \ Lewes, Sussex, June Sth, 1870 (C H. ]'erra/l); Torcross, S. Devon, August 25th, 1903, and Porthcawl, Glamorgan- shire, S. Wales, May 31st, 1903 {Lieiit.-Coloiiel. Yerbury). Colonel Yerbury contributes the following note : — " In the British Isles this seems to be an uncommon insect. It has been caught on the backs of cattle at Barmouth (Merioneth), Porthcawl (Glamorgan- shire), and Torcross (S. Devon). These flies collect in numbers on the withers of young cattle, but are, as may be imagined, difficult to catch. The writer while catching them on the back of one beast got his net hung up on the horns of another, with disastrous consequences to the net. This, or a very closely allied species has the same habits in Ceylon, and was found in great numbers near Trincomali,on the backs of the village cattle." The geographical range of L. irritans doubtless includes the whole of Europe, since it is known to extend from Central Scandinavia to Italy, where, according to Rondani, it attacks horses as well as cattle. The species has been introduced into the United States, where it is stated to have the habit of clustering in masses about the base and on the concave side of the horns of cattle, and has consequentl}- been termed the " Horn-fly." First observed on cattle in New Jersey and Maryland in the summer and autumn of the year 1887, it is said to be now generally distributed throughout the United States and Eastern Canada. The Museum possesses a specimen from Vernon, British Columbia, where it was taken by Miss Ricardo on July 25th, 1902. The species is known to American writers by its synon}-m Hamatobia scrrata, Rob.-Desv. &J Family HIPPOBOSCID^. The strange-looking flies composing this Family are parasitic upon mammals and birds, and are probably descended from ancestors belonging to the Muscid;E, which underwent modification in bodily structure as a consequence of the adoption of a parasitic mode of life. The body in all cases is flattened and horny ; the feet are provided with accessory claws to enable the insect to cling to the hair or feathers of the host ; and while some of the forms, such as the Forest Fly (Plate 31), and Ornithoviyia avicularia, Linn. (Plate 32) are fully-winged, others show a progressive reduction in this respect until in the " Sheep Tick " {Melophagiis oviniis, Linn., Plate 34), the wings are wanting altogether. But even in fully- winged forms, since the flies are true parasites, the wings, as a rule, are made use of merely in order to reach the host, or, in the case of the males, in order to find an indi\ iflual of the opposite sex, and thereafter it is only in exceptional circumstances, such as the death of the host, or too acti\-e pursuit b_\- the human hand, or when taking a short flight from one animal to another, that these flies are ever seen upon the wing. The proboscis in the Hippoboscida; is curved, extremely slender, and protrusible, but is composed of the same parts as that of the blood-sucking Muscida;. In appearance it presents a decided resemblance to the proboscis of the Tsetse-flies, and it also acts in the same way as the latter, its tip being armed with sharp chitinous teeth which enable the organ to pierce the skin of the host. Another point of resemblance to the Tsetse-flics is to be found in the mode of reproduction, which is a further development of the process seen in the flies referred to, and has caused the Hippoboscida: and certain other families of parasitic Di])tera belonging to the same group to receive the name Piipipara. Li these forms, namely, the pregnant female does not lay eggs, but produces at each birth a full-grown larva, which assumes the pupal state iinmediatcl}' after extrusion. In addition to those figured in Plates 31 to 34, the fauna of the 63 British Islands includes two other species of Hippoboscida;, Stenopteryx hiriindhiis, Linn., and Oxypteriim pallidum, Leach, found respectively on and in the nests of the house martin {Cluiidon urbica, Linn.), and the swift {Cypselus apus, Linn.). It is doubtful whether an authentic instance exists in which any species of Hippoboscidje has sucked human blood under natural conditions, though the flies sometimes stray on to human beings when their hosts are interfered with. Genus HIPPOBOSCA, Linn-xu.s. Hippobosca equina, Linn.— The Forest Fly. Plate 31. The upper figure shows the resting position. As indicated b)' the English name, the . principal home of this species in the British Islands is the New Forest, in Hampshire, where it may often be seen in clusters like bees, sometimes numbering many hundreds, on the ponies and cattle which run wild there. The flies chiefly congregate on parts where the skin is thinnest, beneath the tail, on the perinneum, and on the inner surface of the thighs. The bite does not seem to cause pain, and animals bred in the Forest take no notice of the fly, but strange horses and especially donkeys are sometimes driven almost frantic by the irritation caused by a single Forest Fly crawling over them. The toothed claws enable the fly to cling so tightly to the hair that it is impossible for an animal to dislodge it by a brush from its tail, and the quick and somewhat crab-like movements of the insect, which when disturbi.d usually moves sideways, tickle the host and are exceedingly irritating to sensitive animals. Forest flies are to be found from the beginning of May until at least the second week in October. In addition to the New Forest the species 64 occurs in Dorsetshire, and apparent!}- througliout Wales, since tlic Museum possesses specimens from Gl)n}bedd, Cadoxton juxta-Neath, Glamorganshire, S. Wales, October nth, 1898 {^Dr. D. Thomas: on cattle), and others from Beddgelert Valley, Carnarvonshire, N. Wales, July, 1901 {0. Peter: also on cattle). From Dorsetshire there are speci- mens from Corfe Castle, June and July 14th, 1897 iE. R. Bankes), and Bonsley Down, near Blandford, September 25th, 1895 (the late /. C. Ulanscl-Phyddl). In the latter neighbourhood the insect proved troublesome to the army horses engaged in the Autumn Manoeuvres of 1872. The Forest Fly occurs throughout Europe and in verj- man)- other widely distant localities, to some of which, at any rate, it has doubtless been carried with horses in recent years. The Museum collection includes specimens of the species from, — Algeria ; the Cape of Good Hope ; Madeira ; Canary Is. ; St. Michael's, Azores ; Trebizond, Turkej' in Asia ; Bengal ; Upper Burma ; Celebes ; Fiji ; and New Caledonia. Genus ORNITHOMYIA, Latreille. Ornithomyia avicularia, Linn. Plate 32. This species, which is a bird-parasite, is, as might be expected generally distributed throughout the British Islands. The localities of the Museum series of specimens range from the Shetland Islands to Dorset, and include S. Wales and Co. Wicklow, Ireland. The birds from which the flies were obtained were as follows : — pheasant, part- ridge, red grouse, blackcock, snipe, long-eared owl, barn owl, green woodpecker, thrush, blackbird, wheatcar, white-throat, red-backed shrike, and starling. The flics frequently occur singl)-, but sometimes a male and female, or even as many as three specimens, are found on the same bird. If a bird infested by one of these insects be shot, the parasite will sometimes take wing and fly with great pertinacit)- 65 round and round the person carrying the bird. Males whicii have^ perhaps, gone astray while seelcing a female are occasionally met with ; thus at Brockenhurst, in the New Forest, on Ma)' 26th, 1894, '^ male was caught on the wing by Mr. C. O. Waterhouse ; and the Museum collection also contains another male, taken b}- Colonel Yerbury, at Porthcawl, Glamorganshire, S. Wales, on July 1st, 1903, on a hotel window. This species shows great indi\idual variation in size, as also in coloration ; freshly caught or living indi\'iduals arc often quite green. Ornitliomvia avicularia appears to ha\e been carried by birds all over the world ; the Museum possesses specimens from, among other localities, Tristan. d'Acunha I., in the South Atlantic ; Launceston, Tasmania ; and New Zealand. The species also occurs in New South Wales, where, as also in Tasmania, it exhibits a remarkable change of habit, since it is parasitic on the kangaroos known as wallabies {Haliiiatitrns i-nfiioUis, Desm., and H. pariyi, Kenn). CjrENUS LIPOPTENA, 'Nitzsch. Lipoptena cervi, Linn. Plate 33, male : Plate 34, fig. i, female. This species is parasitic upon several species of deer, including the roe, red, and fallow deer, and also, in Scandinavia, upon the elk {Alces alecs, Linn.) ; in Great Britain its chief host is the roe {Capnolus caprcolns, Linn. j. On emerging from the pupa both sexes possess wings, which, in the case of the female at an)- rate, as soon as the insects reach the host appear to break off close to th-e base, leaving stumps as shown in Plate 34, fig. i. Specimens of both sexes found upon a roe are usual!)- in this wingless condition, in which they often present a superficial resemblance to the " Sheep Tick " (^Melopliagus ovinits, Linn. — Plate 34, fig. 2), though the)- can easily be dis- tinguished b)' the possession of wing-stumps. In the autumn months, E 66 however, winged males are sometimes met with in woods inhabited by roe-deer ; these differ considerably in appearance from the apterous males found in company with females among the hair of the host, being paler in colour and more slender in the abdomen, while the males that ha\e lost their wings are more like the females, and are darker in colour with a broader and stouter abdomen. Winged individuals of both sexes have been caught flying round a dead roe, but the females all shed their wings in dying; the Museum collection contains a number of males with wings, but not a single winged female. With two exceptions all the specimens of this species in the Museum series were taken on roe deer at Whatcombe, Blandford Dorset, between September 19th and October 26th, 1895, and presented by the late Mr. J. C. Mansel-Plexdell. Besides these there are also a male from the same locality, taken on October 17th, 1895, on a horse after passing through hazel-bushes in Houghton \\'ood, which is frequented by roe deer (J. C. Mauscl-PlcydcH) ; and another male from Stoke Edith, Herefordshire, caught by Colonel Yerbury, on October nth, 1897, on his own neck, after passing through Stoke Edith Park, in which there are fallow deer. A winged male figured by Curtis (' British Entomology,' 1824) under the name HiEviobora pallipcs, is said to ha\e been taken in the New Forest, Hants, about the middle of September. 1822, on the clothes of a Mr. J. Chant. Lipoptcmi ccji'i doubtless occurs throughout ICuroiJC, and closely allied species are found in other parts of the world. In February, 1901, a specimen of L. a-ti'i was taken by Mr. P. S. Stammwitz, near Johannesburg, Transvaal, under circumstances pointing to the possibility that it had been introduced into South Africa \\ ith remounts durintr the South African War. 67 Genus MELOPHAGUS, Latreille. Melophagus ovinus, Linn. The Sheep " Tick," Slieep " Louse," or Ked. Plate 34, Fig. 2. A higher degree of adaptation to a parasitic existence is exhibited by this species than by any of the foregoing members of the Family to which it belongs, since the wings are always entirely wanting in both sexes. This peculiarity, coupled with the general strangeness of its appearance, which presents little resemblance to an ordinary fl\', and the fact that it passes its whole life-c\-cle in the wool of the sheep, has gained for the insect two of the popular names mentioned above. The late Miss Ormerod (' Report of the Observations of Injurious Insects and Common Farm Pests, during the year 1895 ' (London : Simpkin, Marshall, Hamilton, Kent & Co., Ltd., 1896), p. 120) states that " when seen in the wool " Sheep Ticks " greatly resemble small spiders," though, of course, the presence of onl}- three pairs of legs is sufficient to show that the creatures must be insects. The Sheep Tick does not possess the activity of the Forest Fly, but moves quite slowl}' and quietly through the wool of the host, to which, when not in excessive numbers, it may cause little annoyance. Dr. Parry, however (quoted by Youatt in 'The Mountain Shepherd's Manual' (1862), p. 35), says that JSIclopIiagus oviniis'' is extremely injurious to sheep, by making the animal bite and rub itself, so as not only to hurt the fleece, but to break the skin, in consequence of which the fl}' [Luci/ia sericata, Mg.] is apt to fi.x on the wool near the wounded spot and there deposit its eggs." The Sheep Ticks in the Museum collection were taken during May and June, i.e., at shearing-time, but Curtis belie\-es that the insect is to 68 be found all the year round, since he had received specimens as early as March. Like the Sheep Bot-fly {Gistnis oti's, Linn.) the Sheep Tick has been carried about the world with its host. Recentlj' the Museum has received a series of specimens of this species (with pupa-cases) from Pecos Canon, New Mexico, taken and presented by Dr. M. Grabham, in June, 1903. INDEX. Ague in Great Britain, disappearance of, not dependent on extinction of mos- quitoes, but probably due to several causes, 21. Anopheles, a genus of Culicidiu : .1. bifurcatus (plate 3), distribution of, ]y ; A. mancUfennis, the Spotted CJnat (plate 4), widely distributed and blood- sucking in Great Britain, 20; A. iiigripcs {^^\^Xft 2), distribution of, 18; sometimes found indoors, 1 9 ; distribution of ague dependent mainly on jmme?-ical distribution of Anopheles, 22. Atylotus, a genus of Tabanida; : A.fulvus (plate 18), among the rarer of British Horse-flies, description of, 44 ; specimens in Museum only from Hampshire and Kenmare, 44 ; continental distribution, 44 ; A. rustinis, .even rarer than A. fulviis, distinguished by greyer tint of short hair covering body, 45 ; only one modern British example in Museum from N.E. Essex, 45. BLOOD-stJCKiNG flies among British Diptera, some 74 species found in only six families, 1 2. Breeze-flies, popular name sometimes applied to Tabanidie, 31. Brimps, popular name in Kent for species of Hrematopota, 31. Ceratopogon, a genus of ChironomidK : divisions lately introduced by Kieffer, 14 (note). Chironomid.e (Midges): British blood-sucking forms belong to genus Ceratopogon ; about 50 indigenous species, only a few of these known to suck blood, annoyance caused by and description of, 13; C. pidicaris (plate I, fig. 2), prevalent in certain localities in England in 1904, figure of in resting position, 15 ; distinguished from C. variiis, 16; C. varius (plate I, fig. i), minuteness and range of, 14. 70 Chrvsoi'S, a genus of Tabanidae : C. caciilicns (plate 26), striking sexual difference in coloration and marking of abdomen, beauty of eyes, British specimens in Museum, 5,5 ; in ICngland, commonest species of genus, not plentiful in Scotland, 54 ; almost silent in approach, thus differing from Tabanus, continental specimens in .Museum, 54 ; C. qiiadrata (plate 27), differences between male and female, 54; rare generally in Britain, continental specimens in Museum, 55 ; C. relicta (plate 28), distinguished from C. aeciitiein, description of, common and generally distributed in Great Britain, continental specimens in Museum, 55 ; C. sepukralis, rare in British islands, only three specimens in Museum, description of, continental distribution, 56. Ci.Kcs, ])0[)ular name for species of Tabanidx, 31. CocciD.E (scale-insects), clistinguishctl from gall-midges (Diptera), 11. ClTLEX, a genus of ('ulicidas : C. cantain (plate 6), not very common in Great Britain, 24; C. nemorosiis (plate 7), common in England, not seen in houses or out-buildings, range of, 25 : C. pipiots, the Common Gnat, (plate 8), common in Great Britain, in houses practically throughout the year, 25 ; often found in winter on roofs of cellars, a troublesome blood- sucker, geographical range, 26. CuLiciD.E (gnats or mosquitoes), twenty-two J5ritish species, Ik^v distin- guished from certain midges, 17 ; blood-sucking habit confined to female sex in British mosquitoes, 17; i)reliminary stages of development, 17, iS; British mos([uitoes beside those illustrated, 18. Cui.iroiDKs, a genus of Chironomid:;;, revived by l\.icffer to include Cemto- pogon varius, C. puUcaris, and other species of ("eratopogon, 14 (note). Dark surfaces, predilection of various blood-sucking Diptera {Anopheles, Hcemaiopafa, Lypcrosia) for resting thereon, 60, Oi. DiPTKRA, chief characteristics of, 11 ; fifty-nine families recognised as British in W-rrall's ' List,' 11 ; 2700-_^ooo liritish species, 12. DuN-Ki.iKS, popular name for species of TabanidiU, 31. "Flies," meaning of term, 11; blood-sucking habit in only six British families, 12. Gad-I'LIEs, popular name fretjucntly applied to Tabanida!, 31. 71 Grabhamia, a genus of Culicidas ; G. dorsalis (plate 9), most handsome of British mosquitoes, characteristics of, found as a rule in the southern counties, 26 ; known on the Suffolk coast as the ' Norway Mosquito,' severity and virulence of its bite, 27. H.€MATOBiA, a genus of Muscidce : H. stimulans (plate 33, fig. i) in habits, time of occurrence, and extent of distribution in British Isles, similar to Sfomoxys cakitraiis, but head much smaller and palpi more prominent, 59, 60 ; wide range of distribution in British Isles ; no specimen in Museum from other localities, 60. H.EMATOPOTA, a genus of Tabanida; : individuals sometimes very abundant, 36 ; H. crassicornis (plate 12) closely resembles H. pluvialis, but darker, 35, varying size of, common in many localities, less troublesome in Scotland, 36 ; H. ifa/ica, distinguished by pale femora, and longer antennoe, rarer and more local than other indigenous species, 36, doubt- fully common in Austria, 37 ; H. pluvialis (plate 11), very common and generally distributed, 35. Harvest-buc (Lep/i/s antum/ialis), figure of; swellings caused by, apt to be mistaken for bites of midges or of gnats, 16. HiPPOBOSCA, a genus of Hippoboscidrc : II. equina, the Forest Fly (plate 31), found principally in the New Forest, clustering like bees on the ponies and cattle, bite not painful, Ijut the movements of the insect often irritate animals, 63 ; found also in Dorsetshire and 'Wales, occurs throughout Europe and in many other distant localities, 64. HippoBOSCin.t:, a family of Uiptera, parasitic upon mammals and birds, some fully wmged, others wingless ; resemblance to tsetse-flies in proboscis and mode of reproduction, 62 ; two species found on and in the nests of the house-martin and swift ; doubtful whether any species sucks human blood, 63. ' HoRN-i-Lv,' name given in United States to lyperosia tri-itans, also termed Hamatobia serrata, 61. Horse-flies, popular name for 'I'abanidre, 31. Ked, popular name for Melophagus ovinus, 67. Leptus autumnalis (harvest-bug), figure of; swellings caused by, apt to be mistaken for bites of midges or of gnats, 16. LiPOi'TKNA, a genus of HippoboscicUx; : /-. (•tv?'/ (plates 33 and 34) parasitic on several species of deer, in Great Britain chiefly on the roe, both sexes sometimes wingless, 65 ; differences between winged and wingless males ; nearly all specimens in Museum from roe deer in 1 )orset : occurs throughout Europe, one specimen found in 'l'rans\-;ud, 66. T.YPKROSiA, a genus of Muscidrc : Z. irritans (plate 30, fig. 2) the smallest of native blood-sucking Muscidx', a pest of cattle, especially of black animals, does not attack liuman beings, 60 : uncommon in British Isles : closely allied species found in Ceylon : L. irritans generally distributed throughout Europe, the United States and Eastern Canada ; in the U.S.A. termed the ' Horn-fly,' from habit of clustering about base of horns; also known as Hainatobia st'rra/a : in Italy attacks horses as well as cattle, 61. Meloi'HAuus, a genus of Hippoboscidiii : M. oviniis, the sheep ' tick,' sheep Mouse' or ' ked ' (plate 34, fig. 2), wings completely wanting in both sexes ; whole life-cycle passed in wool of .sheep : as thus seen the insects greatly resemble small spiders : may injure sheep by causing them to bite and rub themselves, thus producing a wound which attracts fly (Liicilia sericata), 67 ; found at all seasons, and recently met with in New Mexico, 68. Musciii.K, a family of I)i[)tcra. containing three British blood-sucking species, nearly allied to common house-fly and to African tsetse- flies. Blood- sucking habit exceptional and confined to very t'ew genera and species, but common to both sexes, 57. Blood-sucking Muscida; (tsetse-flies excepted) l)rced in dung, eggs developing into wiiite maggots, 57. 'NokWAV Mc)sgrn'0," term applied at .Mdeburgh to Grahluimia dormlis, 27. NuTiAi.i,, Cobbett, and Strangeways-I'igg on Aiiopheks and ague in Great Britain, 21, 22. Okni riioMViA, a genus of Hippoboscidiv: O.oviat/oria (plate 32) distributed throughout British island.s, infesting various birds, 64 ; variations in size and coloration ; carried by birds all over the world : in New Soutli ^\'a]es and Tasmania parasitic on wallabies, 65. 'Shkki' tick,' 'sheep louse' or ' ked,' terms applied to Melophagiis (minus, 67. 73 SiMULiD^, a family of Diptera consisting of the single genus Simulium, universally distributed, 28 ; often causes great losses among various animals, especially in United States and Hungary ; description and pre- liminary stages, 28 ; S. hirtipes, a biting pest in Scotland, 30 ; 5. reptans (plate 10), a northern species, description of, 29 ; distribution of, 30. Spotted Gnat (plate 4), otherwise known as Anopheles macnlipoinis, 20. StoiMOXvs, a genus of Muscida; : 6'. calcitrans (plate 29) similar in size to house-fly, but distinguished by proboscis, common in Great Britain, plagues both men and cattle, 58 ; its bite and that of Hamatobia sfimulans more painful to some persons than that of any other fly ; cattle and horses severely bitten in Northumberland in 1865, 59; geo- graphical range very wide, 59. Stouts, popular name for species of Tabanidse, 31. Tabanid.b (Horse-flies, Breeze-flies, Dun-flies, Clegs, and Stouts, frequently called Gad-flies), a family of Diptera, most formidable in appearance of all blood-sucking flies ; world-wide distribution, twentj'-two recognised species in Great Britain, general appearance, 31 ; common in summer in country places, 32 ; large as well as small animals severely affected in many countries, 2ii '1 petroleum used in Russia for destruction, 2,1 ; description of eggs and larvse, latter carnivorous ; Tabanidse some- times preyed upon by robber-flies, 34. Tabanus, a genus of Tabanida; : T. aiilumnalis (plates 21 and 22), striking sexual difference in marking and coloration of abdomen, 48 ; in South of England one of commonest species of the genus, continental dis- tribution, 48; T. bovinus (plate 19), with T. sudetkits the bulkiest of all British Diptera, 45 ; distinguished from T. sudeticus, 45, 46 ; British specimens in Museum all from Southern counties, continental specimens, habits, 46 ; T. bromiiis (plate 23), common in South of England, easily recognised, dimensions of, British specimens in Museum, 49 ; distri- bution throughout Europe, 50 ; T. cordiger (plate 25), usually rare, but plentiful in Abernethy Forest, Inverness-shire, 51 ; continental distri- bution, 52 ; j; glaucopis, no British examples in Museum, description of, continental specimens, 52 : T. maciilicornis (plate 24), distinguishing characters of, smallest of the British species of Zl, 50 ; very common in South of England, British and continental specimens in Museum, 51 ; 74 T. sudeticus (plate 20), localities and dates of British specimens in Museum, 47 ; found throughout luiroiJC, habits, 48. Theobai.dia, a genus of Culicidre : T. aiiuulata (plate 5), one of the largest of mosquitoes, common in Great Britain at all seasons, hibernates in sheds, cellars, etc., severe effects of bite of, 23 ; can subsist on a vegetable diet, at Weston-super-Mare sometimes spoken of as the " ^\"ood Gnat," 23, 24. Theriopi-ECTES, a genus of Tabanidre : Th. Iwrealis, description of, very few specimens in Museum, 38, 39 ; geographical distribution, 39 ; Th. luridus (plate 15), darker than Th. mo/i/aniis, description of, 40; distribution of, in the British Islands, apparently a northern species, 41 i Th. ;«/(-a:/« (plate 13), description of, legs entirely black, thus distinguished from /lisfgnafi/s form of Th. trophiis, 37 ; very rare in Great Britain, no modern British specimens in Museum, 38 ; Th. monfanus (plate 14), considerable difference between sexes, 39 ; essentially a Scotch and Irish species, 39; distribution in Europe, 40; Th. sohtitialis (plate 17), most brightly coloured of the larger British Tabanidae, very common, and generally distributed in Great Britain, 43 ; continental distribution, 43 ; Th. tropicus (form bisignatus, plate 1 6), the common British form of the female of this species, description of, 41, resembles Th. micans, British specimens in Museum only from England, continental specimens, 42. Woon Gnat, popular name sometimes given at Weston-super-Mare to Thcobaldia annulafa, 24. PLATE 1 Fic;. I. Ceratopogon varius (Female) Fig. 2. Ceratopogon pulicaris (Female) PLATE 2 Anopheles nigripes (Female) PLATE 3 Anopheles bifurcatus (Female) PLATE 4 Anopheles maculipennis (Female) THE SPOTTED GNAT PLATE 5 Theobaldia annulata (Female) PLATE 6 Ciilex cantans fFemale"; PLATE 7 Culex nemorosus (Female) PLATE 8 Culex pipiens (Female) THE COMMON GNAT PLATE 9 ;immmimmsms!iimttasie' Grabhamia dorsalis (Female) UJ < V a. c PLATE 11 Fu;. 1. Haematopota pluvialis (Male) :-ii3a y, tpt rr o^":.^jg ^ii^.W (as&iaJt;4n^^^ - : i i tjipa^> >j^.;.j^p^i^^a5:Sat^;';^ Fig. 2. Haematopota pluvialis (Female) \ PLATE 12 Haematopota crassicornis (Female) UJ H < E c 1) H H < E u _c tl] < E V 3 T3 O a o UJ H < a. a s C be U2 ^ O o -Q en a c rt rt H PLATE 20 Tabanus sudeticus (Female) CM UJ < H CM UJ H < a. s 3 3 C OS ni H CO H < CL e u O u CM LU < -J CL ti S o _o ~5 u e 3 C nj n) H CM UJ H < -1 E 1) o u (fi p c 03 J3 CO f-i PLATE 26 Fig. I. Chrysops caecutiens (Male) Fig. 2. Chry.sops caecutiens (Female) PLATE 27 Chrysops quadrata (Female) PLATE 28 Chrysops relicta (Female) PLATE 29 Stomoxys calcitrans (Female) PLATE 30 Fig. I. Haematobia stimulans (Female) ^w^^^Bmgwm Fig. 2. Lyperosia irritans (Female) t"UA It 1 Hippobosca equina (Female) THE FOREST FLY . CO UJ H < a. H 6 .2 *c 3 u '> n! .5 E o CO CO UJ < -1 0. n) > V (J ca c V +-t a o Q, PLATE 34 Fig. I. Lipoptena cervi (Female) Fig. 2. Melophagus ovimis (Female) THE SHEEP "TICK," OR KED -It '■ ■'■ i'*^%' 4 \ ^ ^o^