REVISION OF STREPSIPTERA PIERCE. 151 



Female. — Length of cephalothorax 0.45 mm., breadth at spiracles 

 0.47 mm., breadth of head 0.228 mm., distance between mandibles 

 0.05 mm. Cephalothorax light yellowish brown, with longitudinal 

 dark-brown band as wide as brood canal and extending from spiracles 

 posteriad, being equally on thorax and abdomen; truncate pyram- 

 idal, constricted at base, widest behind spiracles, rapidly narrowing 

 to mandibles, shallowly concave at base of head, squarely truncate at 

 apex; spiracles lateral but not prominent; mandibles small with 

 apical tooth. 



Type.— Cat. No. 10108, U.S.N.M. 



HALICTOPHILUS, new subgenus. 



7. HALICTOXENOS MANILA, new species. 



Host. — Halictus (Evylxus) manilse Ashmead; Manila, Philippine 

 Islands; Robert Brown, collector; from U. S. National Museum col- 

 lection (pi. 12, fig. 5). 



Female. — Length of cephalothorax 0.608 mm., breadth at spiracles 

 0.65 mm., breadth of head 0.45 mm., distance between mandibles 

 0.08 mm. Cephalothorax yellowish brown, with narrow dark-brown 

 strip at base which extends back over abdomen to form a semicircle; 

 stylopiform, abruptly constricted behind spiracles, convex through- 

 out, very shallowly emarginate at base of head ; head rounded evenly 

 throughout from base to base, not narrowed and truncate as in the 

 preceding species; spiracles not laterally prominent; mandibles 

 broad, apically armed with two blunt teeth. 



Type.— Cat. No. 10112, U.S.N.M. 



8. HALICTOXENOS ROBBII, new species. 



Host. — Halictus {Evylxus) robbii Ashmead; Manila, Philippine 

 Islands; Robb, collector; from U. S. National Museum (pi. 12, fig. 6). 



Female. — Length of cephalothorax 0.608 mm., breadth at spiracles 

 0.608 mm., breadth of head 0.43 mm., distance between mandibles 

 0.07 mm. Cephalothorax yellowish brown, darker on middle of disk; 

 stylopiform, abruptly constricted behind spiracles, widest at spiracles, 

 convex throughout, shallowly emarginate at base of head, evenly 

 rounded in front; spiracles not laterally prominent; mandibles sub- 

 quadrate, with small tooth on inner apical angle. 



Type.— Cat. No. 10111, U.S.N.M. 



22. Genus APRACTELYTRA Pierce (1908). 



Type of genus. — Apractelytra schwarzi Pierce. 



Name derived from axpanzoi (abortive) + ekurpov (elytron) = aborted 

 elytra. , 



Tins genus is characterized by the absence of the cleavage at each 

 side of the base of the oedeagus. The subequal length of the palpal 



