ees! 339 
Here, the third joint of the antenne either borders on an oval or 
is triangular, or is very long and narrow, and almost lanceolate, 
as in 
Rapuwwu, Meig. * 
In the following, or 
Porpuyrops, Merq. tf, 
It is securiform or triangular, and with a hairy seta; the first joint 
is very short or indistinct. In 
Mepererts, Fisc., Meiq., 
This seta is simple, with the first joint distinct and elongated. The 
last joint of the antenne, or the palette, is nearly oval. 
M. Macquart has formed a genus—Hydrophorus—with those spe- 
cies in which the seta is altogether terminal. Those in which the 
insertion is dorsal, alone compose the genus Medeterus ft. 
There, the third joint of the antennze is almost globular. The seta 
is always hairy. If it be terminal, we have the genus Curysotus; 
if it be inserted a little underneath, that of Psitopus; and, finally, if 
it arise lower down or near the base, DiapHorus, which genus, by 
the almost spherical head, nearly entirely occupied by the eyes, in the 
males, appears to us to lead to the family of the Platypezina of 
Meigen. The wings, ocelli, and some other characters drawn from 
the parts of the head, confirm those we have described. We cannot, 
however, enter into similar details here §. 
The Platypezina of M. Meigen, from which Macquart has very 
properly removed the genus Cyrtoma, and to which we unite that of 
Scenopina, and his family of the MrGacepnati ||, consist of Diptera 
very analogous in their proboscis,antenne and wings, to the Doli- 
chopi; but the body is depressed, the head hemispherical and almost 
entirely occupied by the eyes, at least in the males. The palpi are 
turned up or withdrawn, cylindrical or clavate, and resembles those 
of the Notocanthi. The legs are short and spineless, and the pos- 
terior tarsi frequently broad and flattened. 
These Diptera are very small. M. Macquart has furnished us with 
various interesting observations on the habits of several species. 
Some have a seta on the last joint of the antenne. 
Those, in which that seta is terminal, whose eyes are contiguous 
in the males, and the three first joints of whose posterior tarsi, or the 
first at least, are wide and flattened, form the subgenera 
Cattomyta, Jeig., 
Where the first joint alone of the posterior tarsi is dilated, but is as 
long as all the others taken together. 
* Meig. and Macquart. 
+ Idem. 
+ Idem. 
§ Meig. and Macquart. The genus Lonchoptera, arranged by Meigen with the 
preceding genera, is greatly removed from them. See the tribe of the Muscides. 
|| We form them into a small tribe, under the denomination of CRPHALOPSIDES, 
