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; l.a.b.i.al palpi five-segmented, symmetrical; eyes vestigial or wanting. On bats.
(= ISCHNOPSYLLIDae). NYCTERIDIPSYLLIDae
With more or less blunt maxilla; all tibiae 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 antennae 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. Genae of the head and the p.r.o.notum with ctenidia. NEOPSYLLIDae
e. l.a.b.i.al palpi four or five-segmented; symmetrical; hind c.o.xae with patch of spines inside; row of six spatulate spines on each side in front of the antennae. _C. ornate_ found on a California mole. _Corypsylla_
ee. l.a.b.i.al palpi two-segmented, transparent, membranous. On hares. _Spilopsyllus_ Baker
dd. No ctenidium on the head.
e. p.r.o.notum with ctenidium. DOLICHOPSYLLIDae
f. l.a.b.i.al palpi five-segmented, symmetrical.
g. Antepygidial bristles one to three; eyes present.
h. Inner side of hind c.o.xae distally with a comb of minute teeth; falx present. On rodents and carnivores.
_Odontopsyllus_ Baker
hh. Inner side of hind c.o.xae 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. l.a.b.i.al palpi four or five-segmented; asymmetrical (membranous behind), apex acute. _Hoplopsyllus anomalus_ found on Spermophiles in Colorado. HOPLOPSYLLIDae
ee. p.r.o.notum without ctenidium. _Anomiopsyllus californicus_ and _nudatus_ on rodents. ANOMIOPSYLLIDae
cc. Very short fleas; flagellum of the antenna with pseudo-segments coalescent; thorax much shorter than the head and than the first tergite. HECTOPSYLLIDae
Flagellum of the antenna with six coalescent pseudo-segments; maxilla blunt. The chigger on man (fig. 93). D. PENETRANS. (= RHYNCHOPRION = SARCOPSYLLA) DERMATOPHILUS Guerin
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 p.r.o.notum with ctenidium; l.a.b.i.al palpi asymmetrical.
ARCHaeOPSYLLIDae
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 p.r.o.notum with ctenidium. l.a.b.i.al palpi asymmetrical, membranous behind. PULICIDae
e. Mesosternite narrow, without internal rod-like thickening from the insertion of the c.o.xae upwards. Human flea, etc.
PULEX L.
ee. Mesosternite broad with a rod-like internal thickening from the insertion of the c.o.xae upwards (fig. 89). X.
(LMOPSYLLA) CHEOPIS, plague or rat flea. XENOPSYLLA
cc. Thorax much shorter than the head and than the first tergite.
ECHIDNOPHAGIDae. E. GALLINACEA, the hen flea also attacks man (fig. 96). (= ARGOPSYLLA = XESTOPSYLLA) ECHIDNOPHAGA Olliff.
FOOTNOTES:
[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 a.s.sistant have been bitten by LYGUS PRATENSIS, the tarnished plant bug, by CHLAMYDATUS a.s.sOCIATUS 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 Tabanidae is adapted from one given by Miss Ricardo.
[J] The cla.s.sification 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 _Cordyluridae_; (i.e.
_Acalyptratae_) which might be placed with the _Anthomyiidae_ (i.e.
_Calyptratae_), owing to the relatively large size of their squamae. 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 p.u.b.escent, or the eyes of the male nearly or quite contiguous, or the eyes hairy, or the frontal setae decussate in the female; or any combination of these characters may at once be placed with the _Anthomyiidae_. 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 squamae of moderate size which have either no vibrissae, or have the subcosta either wholly lacking or coalescent in large part with R_1 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_.