64 
STUDIES IX AMERICAN EPIIYDRIDAE (DIPTERA) 
male abdomen, the study of the species of the fiircnta-^vowp of 
Xotiphila will soon convince one that such characters are of no 
generic value. The species of that group do not in any way 
resemble the species of this genus, except in the spinose develop- 
ment of the male abdomen. 
Description. — Dark, robust species, similar to Notiphila in most of its char- 
acters. Differing as follows: The anterior proclinate fronto-orbital bristle 
stout and well developed. Face flattened or weakly carinate above, with the 
median area below broader in proportion to the facalia and orbits; the facalia 
is very narrow, distinguished as a ridge hardly wider than the bases of the three 
to four stout facial bristles. The pleura has a more or less stout, upcurv^ed 
bristle just above the fore coxae; the abdomen is more shining, sometimes 
polished, with at most only the apical margins of the segments faintly lighter 
in color; fifth segment of the males of all known species is more or less conically 
developed, often into a cylindrical prolongation or tubercle bearing two long, 
approximated, up-curved bristles at the tip; apical margin of fourth segment 
more or less reflexed, with a subapical series of very long bristles. Middle 
femora of both sexes with three extensors. 
Genotype. — Notiphila caudata Fallen (moiiotypic). 
Notes. — The study 1 have given my material convinces me 
that the amount of development of the conical apex of the fifth 
abdominal segment, and the number of bristles on the fourth of 
the males of this genus are of no specific value. I have a series 
of twenty-six males showing all intergrades between a simple 
conically shaped segment, and that with a long, cylindrical tubercle 
as long as the segment, and from six to thirteen bristles on the 
fourth segment. In this series I find that the number of hairs on 
the arista also varies inconsistently. Therefore Loew’s brevicauda, 
if not distinct in other respects, is probably merely a synonym of 
caudata. As brevicauda was described from Europe, and not hav- 
ing seen specimens, I am not prepared to certify this synonymy. 
Becker does not given any characters which are not invalidated 
by the above mentioned study, so no help can be derived from 
that source. The extremes of my series show slight variation in 
size and color; the brevicauda form being smaller, darker and 
more shining, while the other extreme is more opaque and varied 
with light marks and stripes. However these differences are not 
constant in either form. There is also no correlation in the 
geographical distribution, as either form may be found in the 
same locality. The females are similar in every respect. 
