380 INSECTA. 
designated this last genus by the name of Chrosomyza, We will 
unite these two genera in the single subgenus 
Mosiutus, Lat. 
I have cften found numbers of the M7. arcuatus on the dust of old 
walls*, 
Those species, in which the first cells of the posterior edge of the 
wings are entirely open and longitudinal, composed, in the work of 
Meigen, two other genera: 
Homarons, where the abdomen presents five segments, and Ac- 
rora, where it exhibits six. The head is still more comp:essed than 
in the preceding subgenera. The seta, according to him, is naked, 
but I have seen it plumous in some specimens}. 
There, the attennz are almost contiguous; the cells of the poste- 
rior edge of the wings are always open 
Those Gymuomyzides in which the attenne are very short, and 
inserted, as in the last subgenus, under a sort of arch and near the 
middle of the face, form the genus Gymnomyza of Fallent. Those 
in which these organs are inserted higher up, without any distinct 
appearance of an arch at their origin, and that terminate in an elon- 
gated palette, comp.se the genus LoncumA of Fallen and Meigen. 
According to the latter the front is narrower in the males than in the 
females, and we see by their character that these Insects are con- 
nected in scme respects with various species of Anthomyze§. The 
antenne of the Celyphi and Lauxaniz are also inserted higher than 
in the other Gymnomyze. 
Our second section of the Muscides, which will form our ninth 
and last sub-tribe or general division, that of the Hypocera, com- 
prises but a single subgenus, very distinct from the preceding ones 
in several characters. The palpi are always exterior; the antennz 
inserted near the oral cavity are very short, and terminated by a 
thick and almost globular joint, with a very long seta. The wings, 
whose edge is densely ciliate superiorly, present near the base a stout 
oblique nervure, which extends to the margin where this stigma 
is ce in the Hymenoptera, and from this nervure proceed three 
others which run almost parallel with each other, in a longitudinal 
direction; hence the origin of the name 7'rineura, given to this sub- 
genus by M. Meigen. The body is arcuated, the legs stout and 
spinous, and their thighs large and compressed, the posterior ones 
particularly. These Insects are extremely vivacious, and form in 
our * Genera” the genus 
Puora, Lat.—Trinevra, Merg. 
In the Diptera of which we have hitherto spoken, we have found a 
sucker received into the superior canal of a tubular sheath, more or 
less membranous, geniculate at base, most frequently terminated by 
* See Lat., Gen. Crust. et Insect, 1V, 357; Meig., et Fallen. 
+ See Meigen. 
t Fallen, Dipt. 
§ Fall. and Meigen. 
