a. Proboscis long, directed forward, adapted for piercing, or oral margin much produced, snout-like.
b. Oral margin produced snout-like; vibrissa placed high above the oral margin; antennal arista either pectinate or more or less plumose.
c. Antennal arista short or long-plumose; neither sex with distinct orbital bristles.
d. No facial carina between the antennæ. Rhynchomyiinæ
e. Arista short-plumose. R. speciosa. Europe. Rhynchomyia R. D.
ee. Arista long-plumose. I. phasina. Europe and Egypt. Idiopsis. B. B.
dd. With flattened carina, the bases of the antennæ separated; no abdominal macrochætæ. Cosmininæ
C. fuscipennis. South Africa. Cosmina
cc. Antennal arista pectinate; bases of the antennæ separated by a flattened carina. Rhiniinæ R. D.
d. Cell R5 open, or closed at the margin.
e. Third segment of the antenna twice as long as the second; claws of both sexes short; cell R5 open. I. lunata. Eastern Hemisphere. Idia Meigen
ee. Third segment of the antenna three times as long as the second; cell R5 open or closed; claws of the male long and slender, of the female shorter than the last tarsal joint. I. mandarina, China. Idiella B. B.
dd. Cell R5 petiolate. Rhinia; and Beccarimyia Rdi.
bb. Proboscis long, directed forward, adapted for piercing. Stomoxinæ
c. Arista flat, pectinate above with plumose rays; sternopleurals 1:2; bases of the veins R1 and R4+5 without setæ; base of the media bowed down; apical cell opens before the apex of the wing. African species Glossina Wied.
d. Species measuring over twelve mm. in length. G. longipennis and fusca.
dd. Species less than twelve mm. in length.
e. All segments of the hind tarsi black.
f. The fourth and fifth segments of the fore tarsi black; antennæ black (fig. 164). G. palpalis R. D.
ff. Otherwise marked. G. bocagei, tachinoides, pallicera.
ee. First three segments of the hind tarsi are yellow, the fourth and fifth segments are black.
f. Fourth and fifth segments of the first and second pair of tarsi are black.
g. The yellow bands of the abdominal segments occupy a third of the segment (fig. 165). G. morsitans Westw.
gg. The yellow band on each segment of the abdomen occupies a sixth of the segment. G. longipalpis Wied.
ff. Tarsi of the first and second pairs of legs wholly yellow. G. pallidipes Austen
cc. Rays of the arista not plumose; only one or two sternopleurals; base of the media not strongly bowed down; apical cell opens at or very near the apex of the wing.
d. Vein R4+5 without setæ at the base; palpi about as long as the proboscis.
e. Arista pectinate (i. e. rays on one side only), the rays often undulate; two yellow sternopleurals often difficult to detect; vein M1+2 only slightly bent, the apical cell hence wide open. The horn fly, H. irritans (= Lyperosia serrata) and related species. Widely distributed (figs. 167, 168). Hæmatobia R. D. not B. B.
ee. Arista also with rays below; vein M1+2 more strongly bent, the apical cell hence less widely open.
f. Palpi strongly spatulate at the tips, lower rays of the arista about six in number, B. sanguinolentus. South Asia. Bdellolarynx Austen
ff. Palpi feebly spatulate; apical cell of the wing narrowly open slightly before the tip; sternopleurals black, anterior bristle sometimes absent. H. atripalpis. Europe. Hæmatobosca Bezzi
dd. Vein R4+5 with setæ at the base.[L]
e. Veins R1 and R4+5 with setæ at the base; two equally prominent sternopleural macrochætæ; arista with rays both above and below; palpi as long as the proboscis; apical cell of the wing wide open. L. tibialis. (Hæmatobia B. B. not R. D.). Lyperosiops Town.
ee. Only vein R4+5 with basal setæ; anterior sternopleural macrochæta wanting; arista pectinate.
f. Palpi as long as the proboscis, the latter stout, with fleshy terminal labellæ; apical cell narrowly open; sternopleural macrochætæ black. S. maculosa from Africa and related species from Asia. Stygeromyia Austen
ff. Palpi much shorter than the proboscis, the latter pointed at the apex, without fleshy labellæ; apical cell of the wing wide open. S. calcitrans, the stable fly and related species. Widely distributed in both hemispheres (fig. 110). Stomoxys Geof.
aa. Proboscis neither slender nor elongate, the labellæ fleshy and not adapted for piercing.
b. Hypopleuræ without a vertical row of macrochætæ. Muscinæ
c. Arista bare; distal portion of R4+5 broadly curved at the end; hypopleuræ with a sparse cluster of fine hairs. S. braziliana, Southern States and southward. Synthesiomyia B. B.
cc. Arista pectinate or plumose.
d. Arista pectinate. H. vittigera, with the posterior half of the abdomen metallic blue. Mexico. Hemichlora V. d. W.
dd. Arista plumose.
e. Middle tibia with one or more prominent setæ on the inner (flexor) surface beyond the middle, or inner surface very hairy.
f. R1 ends distad of the m-cu crossvein; R4+5 with a broad curve near its apical end. (= Neomesembrina Schnabl. = Metamesembrina Town). M. meridiana. Europe. Mesembrina Meigen
ff. R1 ends proximad of the m-cu crossvein.
g. Eyes pilose, sometimes sparsely in the female.
h. Female with two or three stout orbital setæ; the hind metatarsus of the male thickened below at the base and penicillate. D. pratorum. Europe. Dasyphora R. D.[M]
hh. Neither sex with orbital setæ.
i. Abdomen without macrochætæ; arista plumose. C. asiatica. Eastern Hemisphere. Cryptolucilia B. B.
ii. Abdomen with strong macrochætæ; arista very short-plumose, nearly bare. B. tachinina. Brazil. Reinwardtia B. B.
gg. Eyes bare.
h. Body densely pilose; thoracic macrochætæ wanting; middle tibiæ much elongate and bent; last section of R4+5 with a gentle curve. H. (Mesembrina) mystacea, et al., Europe and H. solitaria, N. America. Hypodermodes Town.
i. Dorsocentrals six; last section of R4+5 with a gentle curve.
j. Inner dorsocentrals ("acrostichals") wanting; sternopleurals arranged 1:3. P. cyanicolor, cadaverina, etc. Europe and America. Pyrellia R. D.
jj. Inner dorsocentrals ("acrostichals") present; sternopleurals arranged 1:2. E. latreillii. North America. Eumesembrina Town.
ii. Dorsocentrals five; inner dorsocentrals present; last section of R4+5 with a rounded angle; sternopleurals arranged 1:2. P. cornicina Europe and America. (Pseudopyrellia Girsch.) Orthellia R. D.
ee. Middle tibia without a prominent bristle on the inner surface beyond the middle.
f. Squamula thoracalis broadened mesad and caudad as far as the scutellum.
g. Sternopleural macrochætæ arranged in an equilateral triangle; front of both sexes broad; genæ bare; dorsocentrals six, small; wing not rilled. (To Coenosinæ). Atherigona Rdi.
gg. Sternopleural macrochætæ when three are present, arranged in a right triangle.
h. Last section of R4+5 with a more or less rounded angle (fig. 163l).
i. Eyes of the male pilose or pubescent, of the female nearly bare; m-cu crossvein usually at or proximad of the mid-distance between the r-m crossvein and the bend of R4+5. P. (= Placomyia R. D.) vitripennis. Plaxemyia R. D.
ii. Eyes bare; the m-cu crossvein always nearer to the bend of R4+5 than to the r-m crossvein.
j. Apex of the proboscis when extended reveals a circlet of stout chitinous teeth. P. insignis Austen, of India, bites both man and animals. (= Pristirhynchomyia) Philæmatomyia Austen
jj. Apex of the proboscis without black teeth.
k. Eyes of male separated by a distance equal to a fourth the width of the head. House or typhoid fly. M. domestica L. Widely distributed. Musca L.
kk. Eyes of the male contiguous. E. corvina. Europe. Eumusca Town
hh. Last section of R4+5 with a gentle curve (fig. 102).
i. Eyes pilose.
j. Claws in the male somewhat elongated; no orbitals in either sex; antennæ separated at the base by a flat carina; abdomen marked with red or yellow. G. maculata. Europe and America. Graphomyia R. D.
jj. Claws short and equal in the two sexes; two or three stout orbital macrochætæ in the female; R1 scarcely produced beyond the r-m crossvein; eyes contiguous in the male. P. obsoleta. Brazil. Phasiophana Br.
ii. Eyes bare; fronto-orbital macrochætæ in a double row, antennæ contiguous at the base.
j. One or more pairs of well developed anterior inner dorsocentral (acrostichal) macrochætæ; seta on extensor surface of hind tibia. M. assimilis, stabulans, etc. Europe and America. Muscina R. D.
jj. Anterior inner dorsocentrals and the setæ; on the extensor surface of the hind tibia wanting. M. micans, etc. Europe and North America. Morellia R. D.
ff. Squamula thoracalis not broadened mesad and caudad, not reaching the margin of the scutellum; macrochætæ on extensor surface of the hind tibia wanting.
g. Eyes pubescent. M. meditabunda. Europe and America. Myiospila Rdi.
gg. Eyes bare; R1 ends before the middle of the wing. A number of species from the tropics of both hemispheres. Clinopera V. d. W.
bb. Hypopleuræ with a vertical row of macrochætæ.
c. Eyes pubescent.
d. R1 ends about opposite the r-m crossvein; basal section of R4+5 bristly nearly to the crossvein; S. enigmatica. Africa. Somalia Hough
dd. R1 ends distad of the r-m crossvein.
e. Eastern hemisphere. Australasia. N. ochracea, dasypthalma. Neocalliphora Br.
ee. Western Hemisphere. T. muscinum. Mexico. Tyreomma V. d. W.
cc. Eyes bare.
d. The vibrissal angle situated at a noticeable distance above the level of the margin of the mouth.
e. Sternopleural macrochætæ arranged in the order 1:1.
f. Genæ with microchætæ.
g. Body grayish, with depressed yellow woolly hair among the macrochætæ; wings folded longitudinally over the body when at rest. Cluster flies. P. rudis and related species, widely distributed. Pollenia R. D.[N]
gg. Body metallic blue or green. Eastern Hemisphere.
h. Vibrissal angle placed very high above the oral margin; a carina between the antennæ; outer posthumeral wanting; anterior intraalar present. T. viridaurea. Java. Thelychæta Br.
hh. Vibrissal angle moderately high above the oral margin; carina small or wanting; no post humeral macrochæta; lower squamæ hairy above. (= Paracompsomyia Hough) (fig. 166). Pycnosoma Br.
ff. Genæ bare. S. terminata. Eastern Hemisphere. Strongyloneura Bigot
ee. Sternopleurals arranged 2:1.
f. Body metallic green or blue, with gray stripes; genæ hairy to the lower margin; post humerals often wanting; lower squamæ bare above. (= Compsomyia Rdi.). Chrysomyia R. D.
g. With one or two orbitals; height of bucca less than half the height of the eye. South and east U. S. (fig. 107). C. marcellaria
gg. No orbitals; height of bucca about a third less than height of eye. West U. S. C. wheeleri Hough
ff. Body black or sordidly metallic greenish gray, usually yellow pollinose or variegate; genæ at most hairy above. N. stygia. Eastern Hemisphere. Neopollenia Br.
dd. Vibrissal angle situated nearly on a level of the oral margin.
e. Species wholly blackish, bluish, or greenish metallic in color.
f. First section of R4+5 with at most three or four small bristles at the immediate base.
g. The bend of R4+5 a gentle curve; costal spine present; cell R5 closed, ending before the apex of the wing. S. cuprina. Java. Synamphoneura Bigot
gg. Bend of R4+5 angular; or the insect differs in other characters; dorsal surface of the squamula thoracalis hairy (except in Melinda); arista plumose only on the basal two-thirds (except usually in Calliphora and Eucalliphora).
h. Arista plumose only on the basal two-thirds.
i. Base of the antennæ ventrad of the middle of the eye; eyes of the male nearly contiguous; genæ hairy; second abdominal segment with median marginal macrochætæ; two, rarely three, postsutural intraalar macrochætæ.
j. Squamula thoracalis dorsally with long black hairs; male hypopygium two-segmented, large, projecting; claws and pulvilli of the male elongate; three strong sternopleural macrochætæ; genæ at least half the width of the eye; buccæ (cheeks) half the height of the eyes; oviviparous. O. sepulcralis. Europe. Onesia R. D.
jj. Dorsal surface of the squamula thoracalis bare; male hypopygium small, scarcely projecting below; claws and pulvilli not elongate; two stout sternopleural macrochætæ, sometimes with a delicate one below the anterior; genæ nearly linear in the male; buccæ about a third of the eye height; oviparous. M. cærulea. Europe. Melinda. R. D.
ii. Base of the antennæ dorsad of the middle of the eye; eyes of both sexes distinctly separated; dorsal surface of the squamula thoracalis with black hairs; two postsutural intraalar macrochætæ.
j. Hypopygium of the male large, with a pair of slightly curved forceps whose ends are concealed in a longitudinal slit in the fifth ventral sclerite; third posterior inner dorso-central (acrostichal) macrochætæ absent; anterior intraalar rarely present; abdomen usually not pollinose; the second segment without median marginal macrochætæ; face yellow. C. mortuorum, cadaverina, and related species. Both hemispheres. Cynomyia R. D.[O]
jj. Three pairs of posterior inner dorsocentrals (acrostichals) present; second abdominal segment with a row of marginal macrochætæ; genæ hairy, at least above.
hh. Arista usually plumose nearly to the tip; posterior dorsocentrals and inner dorsocentrals (acrostichals) well developed; dorsal surface of the squamula thoracalis hairy; abdomen metallic and usually pollinose; genæ hairy.
i. With one pair of ocellar macrochætæ. C. vomitoria, erythrocephala, viridescens, and related species. Both hemispheres. Calliphora R. D.
ii. With two strong pairs of ocellar macrochætæ. E. latifrons. Pacific slope of the U. S. Eucalliphora Town.
ff. First section of R4+5 bristly near or quite half way to the small crossvein; dorsal surface of the squamula thoracalis is bare; the hypopygium of the male is inconspicuous.
g. Genæ bare; posterior inner and outer dorsocentrals distinct and well developed. L. cæsar, sericata, sylvarum, and related species. Widely distributed in both hemispheres (fig. 103). Lucilia R. D.
gg. Genæ with microchætæ, at least down to the level of the base of the arista.
h. Mesonotum flattened behind the transverse suture.
i. Posterior dorsocentrals inconstant and unequally developed; one pair of posterior inner dorsocentrals. P. terrænovæ. North America. Protophormia Town.
ii. Posterior dorsocentrals well developed, the inner dorsocentrals (acrostichals) unequally developed. P. azurea, chrysorrhœa, etc. Europe and America. Protocalliphora Hough
hh. Mesonotum not flattened behind the transverse suture; posterior inner and outer dorsocentrals inconstant and unequally developed. P. regina. Europe and America. Phormia R. D.
ee. Species more or less rufous or yellow in color.
f. Anterior dorsocentrals wanting; first section of the R4+5 at most only bristly at the base, bend near apex rectangular, R1 ends over the crossvein; fronto-orbital macrochæta absent; eyes of the male contiguous. C. semiviridis. Mexico. Chloroprocta V. d. W.
ff. With another combination of characters.
g. Body robust, of large size, abdomen elongate, not round; genæ with several ranges of microchætæ; vibrissal ridges strongly convergent; abdomen with well developed macrochætæ; costal spine usually absent; eyes of the male widely separated.
h. Peristome broad, pteropleural macrochætæ distinct; one or two sternopleurals; in the female a single orbital macrochæta; last abdominal segment without discal macrochætæ; hypopygial processes of the male with a long stylet; second abdominal segment of the female sometimes much elongate. A. luteola (fig. 86). Africa. The sub-genus Chœromyia Roub. is included here. Auchmeromyia B. B.
hh. Peristome narrow; no pteropleurals, two sternopleurals; two orbitals in the female; second segment not elongate; the fourth with two well developed discal macrochætæ. B. depressa. Africa. Bengalia R. D
gg. With another combination of characters.
h. Costal spine present; body in part black; antennæ noticeably shorter than the epistome, inserted above the middle of the eye and separated from each other by a carina; abdominal segments with marginal macrochætæ; sternopleurals 2:1 or 1:1. Paratricyclea Villen.
hh. Costal spine not distinct, or if present, insect otherwise different.
i. Genæ with several ranges of microchætæ; vibrissal ridges strongly converging; peristome broad; arista moderately plumose; sternopleurals usually 1:1; color entirely testaceous. C. anthropophaga (fig. 87) and grunbergi. Africa. Cordylobia Grünb.
ii. Genæ bare or with but one range of setæ; vibrissal ridges less converging; peristome narrow; arista long plumose.
j. Genæ with a single row of microchætæ.
k. Sternopleurals 2:1; color entirely testaceous. Ochromyia Macq.[P]
kk. Sternopleurals 1:1. P. varia Hough. Africa. Parochromyia Hough
jj. Genæ bare.
k. Basal section of R4+5 bristly only at the immediate base, distal section with a broad curve; distal portion of the abdomen metallic; sternopleurals usually 1:1, rarely 2:1. M. æneiventris Wd. Tropic America. Mesembrinella. G. T.
kk. R4+5 bristly at least nearly half way to the small crossvein; sternopleurals 1:1.
l. Macrochætæ of the abdomen marginal; neither sex with orbitals; no carina between the base of the antennæ; three pairs of presutural inner dorsocentrals. Eastern hemisphere. T. ferruginea. Tricyclea V. d. W. (= Zonochroa B. B. according to Villeneuve 1914).
ll. Abdomen without macrochætæ; wing usually with a marginal streak and gray markings. Brazil Hemilucilia B. B.
Adapted from a table published by Oudemans.
a. Elongated fleas, with jointed (articulated) head, with combs (ctenidia) on head and thorax; with long, oval, free-jointed flagellum of the antenna (fig. 92d). Suborder FRACTICIPATA
b. With ctenidia in front of the antennæ and on the genæ (cheeks); maxillæ with acute apices; labial palpi five-segmented, symmetrical; eyes poorly developed or wanting. On rodents. Hystrichopsyllidæ
c. Abdominal segments without ctenidia.
d. Post-tibial spines in pairs and not in a very close set row; head with ctenidia. Ctenophthalmus Kol.
dd. Post-tibial spines mostly single and in a close set row. Ctenopsyllus and Leptopsyllus. The last genus has recently been erected for L. musculi, a widely distributed species occurring on rats and mice.
cc. Abdominal segments with one or more ctenidia; post-tibial spines in numerous, short, close-set transverse rows on posterior border with about four spines in each row. H. americana. Hystrichopsylla Taschenb.
bb. With only two pairs of subfrontal ctenidia; labial palpi five-segmented, symmetrical; eyes vestigial or wanting. On bats. (= Ischnopsyllidæ). Nycteridipsyllidæ
With more or less blunt maxilla; all tibiæ with notch; a single antepygidial bristle; metepimeron without ctenidium. N. crosbyi from Missouri was found on bats. Rothschild suggests that this is probably the same as N. insignis. (= Ischnopsyllus = Ceratopsyllus), Nycteridiphilus
aa. Head not jointed, i.e. the segments coalescent, traces of the segmentation still being visible in the presence of the vertex tubercle, the falx (sickle-shaped process), and a suture. Suborder INTEGRICIPITA
b. Flagellum of the antennæ long and oval.
c. Usually elongate fleas, with a free-segmented flagellum of the antenna; thorax not shorter than the head, longer than the first tergite.
d. Genæ of the head and the pronotum with ctenidia. Neopsyllidæ
e. Labial palpi four or five-segmented; symmetrical; hind coxæ with patch of spines inside; row of six spatulate spines on each side in front of the antennæ. C. ornate found on a California mole. Corypsylla
ee. Labial palpi two-segmented, transparent, membranous. On hares. Spilopsyllus Baker
dd. No ctenidium on the head.
e. Pronotum with ctenidium. Dolichopsyllidæ
f. Labial palpi five-segmented, symmetrical.
g. Antepygidial bristles one to three; eyes present.
h. Inner side of hind coxæ distally with a comb of minute teeth; falx present. On rodents and carnivores. Odontopsyllus Baker
hh. Inner side of hind coxæ without comb or teeth. Many North American species on rodents. Ceratophyllus Curtis
gg. Antepygidial bristles five on each side; eyes absent; suture white. D. stylosus on rodents. Dolichopsyllus Baker
ff. Labial palpi four or five-segmented; asymmetrical (membranous behind), apex acute. Hoplopsyllus anomalus found on Spermophiles in Colorado. Hoplopsyllidæ
ee. Pronotum without ctenidium. Anomiopsyllus californicus and nudatus on rodents. Anomiopsyllidæ
cc. Very short fleas; flagellum of the antenna with pseudo-segments coalescent; thorax much shorter than the head and than the first tergite Hectopsyllidæ
Flagellum of the antenna with six coalescent pseudo-segments; maxilla blunt. The chigger on man (fig. 93). D. penetrans. (= Rhynchoprion = Sarcopsylla) Dermatophilus Guérin
bb. Flagellum short, round, free portion of the first segment shaped like a mandolin.
c. Thorax not shorter than the head, longer than the first tergite; flagellum either with free segments or in part with the segments coalescent.
d. Head and pronotum with ctenidium; labial palpi asymmetrical. Archæopsyllidæ
With four subfrontal, four genal, and one angular ctenidia. Widely distributed. Ctenocephalus Kol.
e. Head rounded in front (fig. 92a). Dog flea. C. canis
ee. Head long and flat (fig. 92b). Cat flea. C. felis
dd. Neither head nor pronotum with ctenidium. Labial palpi asymmetrical, membranous behind. Pulicidæ
e. Mesosternite narrow, without internal rod-like thickening from the insertion of the coxæ upwards. Human flea, etc. Pulex L.
ee. Mesosternite broad with a rod-like internal thickening from the insertion of the coxæ upwards (fig. 89). X. (Lœmopsylla) cheopis, plague or rat flea. Xenopsylla
cc. Thorax much shorter than the head and than the first tergite. Echidnophagidæ. E. gallinacea, the hen flea also attacks man (fig. 96). (= Argopsylla = Xestopsylla) Echidnophaga Olliff.
[E] Adapted from Banks, Nuttall, Warburton, Stiles, et al.
[F] Dr. C. W. Stiles considers the species which is responsible for spotted fever distinct from the venustus of Banks, separating it as follows:
Goblet cells about 75 in the male or 105 in the female. Texas. D. venustus.
Goblet cells 157 in the male, or 120 in the female; stigmal plate shaped as shown in the figure (figs. 150 a, b). Montana, etc. D. andersoni.
[G] Professor C. R. Crosby who has been working upon certain capsids states that he and his assistant have been bitten by Lygus pratensis, the tarnished plant bug, by Chlamydatus associatus and by Orthotylus flavosparsus, though without serious results.
[H] Species marked with an * are known to transmit malaria. Species found only in tropical North America and not known to carry malaria have been omitted from this table, but all found in the United States are included.
[I] This table to the North American genera of the Tabanidæ is adapted from one given by Miss Ricardo.
[J] The classification of the Muscoidea as set forth by Schiner and other earlier writers has long been followed, although it is not satisfactory, being admittedly more or less artificial. Within the last two or three decades several schemes have been advanced, that of Brauer and Bergenstamm and of Girschner, with the modifications of Schnabl and Dziedzicki having obtained most favor in Europe. Townsend, in 1908, proposed a system which differs from Girschner's in some respects, but unfortunately it has not yet been published in sufficient detail to permit us to adopt it. From considerations of expediency we use here the arrangement given in Aldrich's Catalogue of North American Diptera, though we have drawn very freely upon Girschner's most excellent paper for taxonomic characters to separate the various groups.
It may sometimes be found that a species does not agree in all the characters with the synopsis; in this case it must be placed in the group with which it has the most characters in common.
[K] There are several genera of flies of the family Cordyluridæ; (i.e. Acalyptratæ) which might be placed with the Anthomyiidæ (i.e. Calyptratæ), owing to the relatively large size of their squamæ. As there is no single character which will satisfactorily separate all doubtful genera of these two groups we must arbitrarily fix the limits. In general those forms on the border line having a costal spine, or lower squama larger than the upper, or the lower surface of the scutellum more or less pubescent, or the eyes of the male nearly or quite contiguous, or the eyes hairy, or the frontal setæ decussate in the female; or any combination of these characters may at once be placed with the Anthomyiidæ. Those forms which lack these characteristics and have at least six abdominal segments (the first and second segments usually being more or less coalescent) are placed with the Acalyptrates. There are other acalyptrates with squamæ of moderate size which have either no vibrissæ, or have the subcosta either wholly lacking or coalescent in large part with R1 or have spotted wings; they, therefore will not be confused with the calyptrates.
[L] Pachymyia Macq. is closely related to Stomoxys. It differs in having the arista rayed both above and below. P. vexans, Brazil.
[M] The genus Eudasyphora Town. has recently been erected to contain D. lasiophthalma.
[N] Nitellia, usually included in this genus has the apical cell petiolate. Apollenia Bezzi, has recently been separated from Pollenia to contain the species P. nudiuscula. Both genera belong to the Eastern hemisphere.
[O] The following three genera are not sufficiently well defined to place in this synopsis. In color and structural characters they are closely related to Cynomyia from which they may be distinguished as follows. Catapicephala Macq., represented by the species C. splendens from Java, has the setæ on the facial ridges rising to the base of the antennæ and has median marginal macrochætæ on the abdominal segments two to four: Blepharicnema Macq., represented by B. splendens from Venezuela has bare genæ, oral setæ not ascending; tibiæ villose; claws short in both sexes; Sarconesia Bigot with the species S. chlorogaster from Chile, setose genæ; legs slender, not villose; claws of the male elongate.
[P] Plinthomyia Rdi. and Hemigymnochæta Corti are related to Ochromyia, though too briefly described to place in the key.
The following directions for fumigating with hydrocyanic acid gas are taken from Professor Herrick's circular published by the Cornell Reading Course:
Hydrocyanic acid gas has been used successfully against household insects and will probably be used more and more in the future. It is particularly effective against bed-bugs, and cockroaches, but because it is such a deadly poison it must be used very carefully.
The gas is generated from the salt potassium cyanid, by treating it with sulfuric acid diluted with water. Potassium cyanid is a most poisonous substance and the gas emanating from it is also deadly to most, if not all, forms of animal life. The greatest care must always be exercised in fumigating houses or rooms in buildings that are occupied. Before fumigation a house should be vacated. It is not necessary to move furniture or belongings except brass or nickel objects, which may be somewhat tarnished, and butter, milk, and other larder supplies that are likely to absorb gas. If the nickel and brass fixtures or objects are carefully covered with blankets they will usually be sufficiently protected.
There may be danger in fumigating one house in a solid row of houses if there is a crack in the walls through which the gas may find its way. It also follows that the fumigation of one room in a house may endanger the occupants of an adjoining room if the walls between the two rooms are not perfectly tight. It is necessary to keep all these points in mind and to do the work deliberately and thoughtfully. The writer has fumigated a large college dormitory of 253 rooms, once a year for several years, without the slightest accident of any kind. In order to fumigate this building about 340 pounds of cyanid and the same amount of sulfuric acid were used each time. In addition to this, the writer has fumigated single rooms and smaller houses with the gas. In one instance the generating jars were too small; the liquid boiled over and injured the floors and the rugs. Such an accident should be avoided by the use of large jars and by placing old rugs or a quantity of newspapers beneath the jars.
Experiments and experience have shown that the potassium cyanid should be ninety-eight per cent pure in order to give satisfactory results. The purchaser should insist on the cyanid being of at least that purity, and it should be procurable at not more than forty cents per pound. The crude form of sulfuric acid may be used. It is a thickish, brown liquid and should not cost more than four or five cents a pound. If a room is made tight, one ounce of cyanid for every one hundred cubic feet of space has been shown to be sufficient. It is combined with the acid and water in the following proportions: