AKT. 20. STUDIES OF THE BITING LICE — EWING. 19 



Described from four females and one male collected on a female 

 skin of Ctenomys colburni (Cat. No. 238122, U.S.N.M.), taken at 

 Huanuluan, Rio Negro, Argentina. This species is easily distin- 

 guished from all others in the genus on account of its long body and 

 slender posterior legs. 



GYROPUS WETMOREI, new species. 



Text figs. 8 and 9. 



A medium-sized, rather stout species. Head about as broad as 

 long; temporal lobes somewhat projecting, with rounded angles; 

 antennal fossae deep, but filled with antennae in repose, the latter 

 somewhat stout with the last segment almost spherical except for 

 the flat, truncate end ; palpi large, extending to the front margin of 

 labrum, the four segments very distinct. Dorsally near the posterior 

 margin, the head bears a transverse row of six large setae. Pro- 

 thorax almost as broad as the head, with anterior margin almost 



Fig. 8. — Gyropus wbtmokei. Postbriok vibw op femur III. 



straight, from each anterior angle of prothorax there arises a large, 

 curved seta. Mesothorax over twice as broad as long and almost as 

 broad as prothorax; its sides strongly divergent posteriorily. Ab- 

 domen about two-thirds as broad as long and clothed with conspicu- 

 ous setae. Gonopods, low semicircular ridges with a fringe of 

 medium-sized setae. Legs almost equally stout, yet the posterior 

 pair is observed to be more slender than the middle pair; femoral 

 tenaculum of leg III (fig. 8) smaller than tenaculum of leg II; claw 

 of tarsus III slightly longer than claw of tarsus II. 



Length, 1.41 mm.; width, 0.55 mm. 



Type host and type locality .—From male skin of Ctenomys^ species 

 (Cat. No. 236336, U.S.N.M. : Biol. Surv. Collection) taken at Tapia, 

 Tucuman, Argentina. 



Type slide.— Q^t. No. 23752, U.S.N.M. 



Description based on two females on type slide, which are a part 

 of a lot of four females and five young taken from a skin of male 

 Ctenomys (Cat. No. 236336, U.S.N.M.: Biol. Surv. Collection) col- 

 lected at Tapia, Tucuman, Argentina, April 11, 1921, by A. Wetmore. 



