HETERONEURIDJE. 



319 



his genera will be found valid eventually. Heteringomyia 

 he diagnoses as differing from Heteroneura in the absence 

 of cruciate bristles (a pair of small bristles toward the 

 middle of the lower part of the front) and the absence of 

 preapical bristle on the tibiae. H.flavipes, lunibalis and 

 valida lack the cruciate bristles, but one of them, (H. 

 lumbalis} has a distinct preapical bristle, so that this 

 character is rendered invalid, or the cruciate bristle char- 



Fig. 127. Heteroneuridae. i, Heteroneura, wing; 2, Heteroneura, 

 head from in front showing arrangement of bristles (Czerny); 3, 

 Heteringomyia, head from in front showing arrangement of bristles 

 (Czerny); 4, Chtztoclusia, head; 5, i'hcctoclusia, wing; 6, Hetero- 

 ncura, head; 7, Clusia, head (Czerny). 



