I38 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 51 



the following characters : Neither sex shows any ventral plates, but 

 the males show a paired plate-like process widened on apex, occupy- 

 ing the position of a ventral plate to the hypopygial segment, and the 

 long fifth or anal segment is shortened to a mere margin on venter 

 by reason of the hypopygial cavity being pushed strongly forward. 

 There are five abdominal segments, the first being rudimentary and 

 greatly shortened. 



