KEVISION OF STREPSIPTERA PIEECE. 147 



Triimgulinid : Length 0.19 mm., length, including stylets, 0.30 mm., 

 breadth of head 0.07 mm., greatest breadth 0.08 mm., breadth of 

 ninth segment 0.05 mm. This triungulinid also belongs to the type 

 represented by Leionotoxenos. 



Type.— Cat. No. 10126, U.S.N.M. 



Named in honor of the late Dr. William IT. Ashmead. 



4. HOMILOPS ABBOTTI, new species. 



Host. — Proterosphex, species, Trong, Lower Siam ; from collection of 

 U. S. National Museum. 



Female. — Length cephalothorax 2.46 mm., breadth at spiracles 

 2.62 mm., breadth of head 1.78 mm., distance between mandibles 

 0.38 mm. Cephalothorax brownish, head lighter; broader than 

 long, constricted at base, broadest just behind spiracles, convex 

 oblique from spiracles to apex, broadly rounding emarginate in front 

 of mandibles; spiracles laterally prominent or at least reaching lat- 

 eral margin; mandibles oblique, apically emarginate with rounded 

 outer angle surpassing the acute curved tooth of the inner angle. 



Named in honor of Dr. W. L. Abbott, its collector. 



Type.— Cut. No. 12668, U.S.N.M. 



3. Subfamily HAJLICTOXElNriN.^: Pierce, 1908. 



Type genus. — Halictoxenos Pierce. 



Parasitic on Halictina?. 



The subf amity includes two genera, as follows: 



21. Halictoxenos Pierce, 1908, parasitic on Halictus; America, Asia. 



22. Apractelytra Pierce, 1908, host unknown; America. 



21. Genus HALICTOXENOS, Pierce (1908). 



Name based on Halictus + Xenos, meaning a xenid parasitic on 

 Halictus. 



Type of genus. — Halictoxenos jonesi, new species. 



The genus is parasitic on Halictus and contains the following 

 species: 



1. jonesi Pierce, parasitic on Halictus, species; Louisiana. 



2. craivfordi Pierce, parasitic on H. hruneri Crawford; Nebraska. 



3. grxnicheri Pierce, parasitic on H. albipennis Robertson; Wis- 

 consin. 



4. versati Pierce, parasitic on H. versatus Robertson; Wisconsin. 



5. zephyri Pierce, parasitic on H. zephyrus Smith; Wisconsin. 



6. sparsi Pierce, parasitic on H. sparsus Robertson; Oklahoma. 



7. manilse Pierce, parasitic on H. manilse Ashmead; Philippines. 



8. robhii Pierce, parasitic on H. roubii Ashmead; Philippines. 



Numerical key to the females. 



In the genus Halictoxenos the female cephalothorax is very greatly 

 narrowed in front, so that a new series of comparative ratios is 



