DESCRIPTIONS AND DETERMINATIONS OF SPECIES 



43 



Enderleinellus osborni n. sp. 



Plate IV, fig. ii ; plate VI, fig. 6; text fig. 15. 



Numerous males and females from several individuals of Citelhis 

 beecheyi douglasi (ground squirrel) (Cazadero and Covelo, Calif.). The 

 species is close to E. suturalis, differing chiefly in the shape of the sternal 

 plate and the size and number of the abdominal spines, which are much 

 fewer and much shorter and stouter. 



Fig. 15. — Enderleinellus osborni n. sp. ; ventral side of terminal abdominal segments, 

 and pleural plates of female. 



Description of the Female. — Total length .6 mm., length of head 

 .18 mm., length of abdomen .35 mm., width of head .1 mm., width of 

 thorax .16 mm., width of abdomen .33 mm. 



In size and general appearance closely resembling E. suturalis. 

 Head, thorax and legs not appreciably different. The sternal plate, how- 

 ever, is longer than wide, four-sided, the lateral margins the longest, 

 and the posterior margin longer than the anterior. Anterior and poster- 

 ior margins slightly convex, lateral margins concave, all the angles 

 rounded. 



First segment of the abdomen with no hairs, second with a median 

 group of one or two and with two near each lateral margin, all being 

 quite short and slender. Third segment with a median group of two or 

 three small spines and lateral group of two long flat spines. Fourth with 



