TWO NEW LICE. 



263 



suck), the legs and thorax (to enable it to cling to the host). 

 The chsetotaxy of the abdomen is as follows : — There are in the 

 median area two hairs in the dorsum of each segment. On the 

 sternum of the last segment there are also two hairs, medially 

 placed. Rest of the ventral surface bare. Pleura? without hairs, 

 except on the last segment, where there is on each side a single 

 long, curved hair, usually in a curl. The spiracles are large. 



Text-fieure 11. 



Polyplax oayrr7ii/nc7ius. Larva, Stage I. X 65. 



Stage II. (Text-fig. 13.) — In external form this stage resembles 

 Stage I. It differs, however, in size (see measurements below) 

 and in the development of minute pleurites on the abdomen. 

 The head, too, is more pixxluced in front of the antenna?, 

 and its front margin is very rounded. The delicacy of struc- 

 ture is much less marked ; the abdominal cuticle is thicker and 

 covered with a great number of triangular denticles with sharp 

 apices. On the abdomen the chsetotaxy is more developed. 

 Medially there are two hairs on both tergum and sternum of 



