68 CALIFORNIA ACADEMY OF SCIENCES. 



Genus Oncophorus Rudow. (Plate xi.) (The generic 



name Oncophorus was proposed by Rudow for a species 



which has since been transferred to another genus, Eury- 



metopus, but Piaget, retaining the generic name, has 



grouped under it a number of species presenting the 



characters following. This genus " sert de transition 



naturelle entre hs genres Docophorus et Nirmus oVune 



-part et les genres Goniodes et Lipeurus d' 'autre part." ) 



Usually small, 2 mm. being a maximum length among the 



known species; varying from broad to slender; head 



conical, clypeus with or without distinct suture, with or 



without signature; antennae differing in the sexes, the 



male antenna longest, and the first three segments with 



or without appendages ; prothorax but little shorter than 



the metathorax; legs short like those of Nirmus; color 



generally dark brown. But few species (eleven) so far 



described. 



Suborder AMBLYCERA. 



With the antennae clavate or capitate, 4-segmented, and 

 with filiform 4-segmented labial palpi. 

 Family Gyropid^:. 



Characters of single genus. 



Genus Gyropus Nitzsch. Infesting mammals, tarsi 

 with one claw; temples produced into angulated pro- 

 cesses; mouth parts on the frontal margin of the head; 

 size, small from .7 to 1.2 mm. 



Family Liotheid^e. 



Infesting birds (see Boopiat); tarsi with two claws; 

 the 4-segmented antennae lying, when not outstretched, 

 in an excavation on the under side of the head. 



Genus Colpocephalum Nitzsch. (Plate xii.) Body 

 varying in size from very small (1 mm.) to large (3 mm.), 

 elongate, oval or elliptical; head usually wider than long 



