1916] 



Ferris — Notes on Anoplura and Mallophaga 



103 



genitalia. The head is entirely destitute of spines and in the form 

 chosen as the type of the species there are six pairs of pleural 

 plates instead of three as in F. pinnata. The specimens from 

 Perognathus formosus, however, have but three pairs of pleural 

 plates although they agree with the type in all other particulars. 

 Further collecting may just- 

 ify the separation of these 

 two forms. The name is 

 from the Latin meaning 

 thorny. 



Host of the type, Perogna- 

 thus calif ornicus. 



Description of female : 

 Length, 1.65 mm.; length of 

 head, .16 mm.; length of ab- 

 domen, 1.15 mm.; width of 

 head, .15 mm.; width of 

 thorax, .16 mm.; width of 

 abdomen, .45 mm. 



Head triangular in shape, 

 rather sharply pointed ante- 

 riorly and with very shallow 

 antennal sinuses. No hairs 

 on either dorsal or ventral 

 side except for a few very 

 small hairs on the anterior 

 margin and about the ros- 

 trum. Antennae set well 

 back from the anterior mar- 

 gin, five-segmented, rather 

 slender and with all the 

 joints subequal in length. 



Thorax about as long as 

 the head and slightly wider, 

 with the lateral margins 

 parallel and nearly straight. 



No hairs on either dorsal or ventral sides. Sternal plate regularly 

 oval in shape. First pair of legs small with slender claw, second 

 and third pairs very large and stout with stout, heavy claw, and 



Fahrenhohia Iribnlosa 

 female. 



nov. ; 



