THE CANADIAN ENTOMOLOGIST 117" 



A CLASSIFICATION OF OUR LIMNEPHILID CADDICE 



FLIES. 



BY NATHAN BANKS, EAST FALLS CHURCH, VA. 



The Limnephilidse are the most prominent family of c^ddice- 

 flies ih temperate regions. Their classification has been largeK 

 based on the spur formula; this is undoubtedly valuable, but as it 

 broke down in places, I have tried many times to find other char- 

 acters. I divided the group into two on the presence or absence- 

 of spines on the under side of the last joint of the hind tarsi. Dr. 

 Ulmer has brought up a few exceptions. Some I believe are due 

 to the fact that the species is wrongly placed, but in certain Chcetop- 

 teryx it does not hold, but when used in connection with the arma- 

 ture of the front tibia?, it is decisive. The venation in this famil>- 

 is most distressingly uniform, and I have found little not already 

 utilized. The large bristles back or inward of the ocelli I have 

 used as of generic value; and the development of the strips of 

 bristles on the mesothorax I also consider important. I had 

 hoped to find more characters in the face, and palpi; and think 

 that the vestiture of face may yet be used with success. However. 

 I present this preliminary table in the hope that its use may dis- 

 cover the weak points and suggest new characters. I am loath 

 to make so many new genera; but I believe that all are distinct 

 groups, and future study may show some of them to be better 

 placed as subgenera. 



Key to the Genera of Limnephilid.e. 



1. Last joint of hind tarsus with one or more distinct (usually 



black) spines beneath ; tibia I always spined to 



base {Limneph iliiKs) 2 ' 



Last joint of hind tarsus without a distinct spine beneath .^ 

 if one is occasionally present, then the tibia I is not spined 

 to base ". {DriisincB) 18- 



2. No prominent macrochseta? behind or inward from ocelli, 



although sometimes hairs much smaller than macrochata?; 



tips of fore wings not obliquely truncate 3- 



At least one prominent macrochseta behind or inward from 

 each ocellus, about equal in size to the macrocha?ta^ of the 

 posterior warts; tips of fore wings often obliquely 

 truncate 13- 



April, 1916 



