234 



Subfamily TRICHOCERINAE 



I have before me a single specimen of the larva of a species of 

 Trichocera. The pupa is unknown to me. 



In many respects the larva resembles that of Rhyphus, but the 

 affinities of the imago are clearly v^ith the Limnobiidae, and for this 

 reason I retain it here, though with some hesitation. 



Trichocera Meigen 



GENERIC CHARACTERS 



Larva. — Head different from that of all other Limnobiidae in 

 having a complete capsule, closely resembling in this respect Ptychop- 

 teridae and Rhyphidae, the ventral surface especially resembling that 

 of the latter; mandibles stout, with distinct teeth. Body covered with 

 decumbent pile. Prothorax with distinct spiracles. The apical seg- 

 ment is noticeably more slender than the preceding one and armed with 

 4 finger-like processes surrounding the spiracles. 



Pupa. — Head and thorax with hairs much as in Rhyphidae, the 

 cephalic hairs very similar to those of Limnophila. The thoracic re- 

 spiratory organs are horn-like. The abdomen is armed as in Limnoph- 

 ila and has incisions similar to those present in that genus. 



Imago. — See key to subfamilies. 



HABITS OF LARVAE 



The larvae are found in decaying vegetation and under leaves. 



HABITS OF IMAGINES 



The genus Trichocera contains the so-called "winter-gnats" of 

 Europe. They fly in mild weather throughout almost the entire winter 

 in Britain, and are frequently seen flying over snow and settling upon 

 it where the sun falls on it. 



It is remarkable that this very common genus is unrepresented in 

 the materials in our Illinois collection. 



Trichocera sp. ? 



Larva (PI. XXXVI, Fig. i). — Length, 7.5 mm. Pale testaceous, 

 the head with brown marks on each side of central sclerite of dorsum 

 in front of antennae, and along posterior margin. 



Antenna small, consisting of a slender apical process situated on 



