232 INSECTA. 
ing in abutton. The larva of the latter sex has four false feet, 
two near the head, and the rest at the posterior extremity of the 
body(1). 
Sometimes the antennz, always composed of at least thirteen joints 
in both sexes, and for the most part granose, are merely furnished 
with short sete, or at most, and in the males only, with a bundle of 
hairs at base. They form our Tipules gallicoles. 
Crratopocon, Meig.—Ceratopogon, Culicoides, Lat. 
Where the antenne are simply furnished with a bundle of hairs at 
base. 
Their proboscis, as in the two following subgenera, resembles a 
pointed rostrum. The wingsare incumbent. The larve live in ve- 
getable galls(2). : 
Psycuopa, Lat. Meig. 
Without any tuft or bundle of hairs on the antennz; wings tecti- 
form and furnished with numerous nervures. 
The front of the thorax, in one species of this subgenus, has 
two appendages which appear to us to be formed by the lateral 
extremities of its first segment(3). 
Crcrpomyia, Meig. 
Where the antennz, like those of the Psychodz, are granose and 
simply furnished with short, verticillated hairs, but where the wings 
are incumbent on the body, and present but three nervures(4). 
(1) The same, and the Monograph of M. Fallen. 
(2) Lat., and Meig., Ibid. 
(3) Lat., and Meig., Ibid. 
(4) Meig., Dipt., I, 93. See also the Jour. Ac. Nat. Sc. of Philad., Oct. 1817. 
M. Macquart—Dipt. du nord de la France—places his new genus Lestremia di- 
rectly after Cecidomyia. The antennz are hairy, curved forwards, not quite so 
long as the body, and composed of fifteen globular joints, pediculated in the 
males. The legs are long and slender, and the first joint of the tarsi is elongated. 
The Cecidomyia destructor, described and figured in the above journal, may very 
probably belong to this new subgenus, as the antenne seem to indicate. The 
Macropezz are also closely allied to these Diptera. 
