ii8 Book-lice and Bark-lice; Biting Bird-lice 



becula, triangular membranous processes projecting laterally from the head and situated 

 one in front of each antenna; temples, the hinder lateral parts of the head; ocular emar- 

 gination, a bending in of the lateral margins of the head just in front of the eyes; labral 

 lobes, short blunt membranous processes projecting laterally from near the front angles 

 of the head; sternal markings, blackish markings, bars or spots, on the ventral aspect of 

 the thorax. 



Key to Suborders of Mallophaga. 



With short slender 3- or 5-segmented, exposed antenna;; no palpi; mandibles 



vertical Ischnocera. 



With short clavate or capitate, 4-segmented antenna; concealed in shallow cavities 

 on under side of head; 4-segmented palpi; mandibles horizontal. 



Amblycera. 

 Key to Genera of the Suborder Ischnocera. 

 A. With 3-segmented antenna;; tarsi with one claw; infesting mammals only (family 



Trichodectida) Trichodectes. 



AA. With 5-segmented antenna;; tarsi with two claws; infesting birds only (family 

 Philoplerida^). 

 B. Antenna; alike in both sexes. 



C. Front deeply angularly notched Akidoproctus. 



CO. Front convex, truncate, and rarely with a curving emargination, but never 

 angularly notched. 

 D. Body broad and short; head with large movable trabecula:. 



E. Forehead with a broad, transverse membranous flap, project- 

 ing beyond lateral margins of the head in the male, barely 



projecting in the female Giebelia. 



EE. Without such membranous flap Docophorus. 



DD. Body elongate, narrow; head with very small or no trabeculje. 



NlRMUS. 



BB. Antenna; differing in the two sexes. 



C. Body wide, elongate oval to suborbicular. 



D. Temples rounded; tip of abdomen with shallow, curbing emargina- 

 tion; antenna; with no appendage; third segment unusually long. 



Eurymetopus. 

 DD. Temples usually angulated; tip of abdomen convex, rarely angularly 

 emarginatcd with two points. 



E. First antennal segment of male large, and sometimes with 

 an appendage; third segment always with appendage. 



Goniodes. 

 EE. First antennal segment of male large, but always without 

 appendage; third segment without appendage. .GONIOCOTES. 

 CC. Body elongate, narrow, sides subparallcl. 



D. Antenna; and legs long; a semicircular depression in front of 



mouth •. Lipeurus. 



DD. .\ntennx and legs short; depression in front of mouth narrow and 

 elongate, extending as a furrow to the anterior margin of the head. 



Oncophohus. 

 Key to Genera op the Suborder Amblycera. 



A. Tarsi with one claw; infesting mammals only (family Gyropidct) Gyropus. 



AA. Tarsi with two claws; infesting birds only (family Liotheidce). 

 B. Ocular emargination distinct, more or less deep. 



