NEW MALLOI'IIAGA. 4I 



ored plate, whose anterior margin, variously notched, 

 roundlv emarginated, truncated or convex, forms the 

 frontal line of the head. The suture separating the cly- 

 peus from the epicranium is usually distinct or unmis- 

 takably indicated, sometimes indistinguishable. The 

 hind-head is usually widest across the temporal region, 

 the temples often being strongly expanded laterally with 

 angulated or rounded margin. The occipital region is 

 usually concave, so that the head sits "-hat-like" on the 

 prothorax. The head presents certain chitinous bands 

 projecting forward from the occipital margin, inwardly 

 from the eves, forward from the bases of the antennae, 

 etc. The presence or absence and the character of these 

 bands are used as distinguishing specific characters, and 

 the bands are named and defined in the Terminology 

 (see ftostca). 



The antennas (figs. 10, n and 12, plate ii) are short, 

 3-, or 4-, or 5 -segmented and vary much in shape and 

 character. They are filiform (suborder Ischnocera) or 

 clavate or capitate (suborder Amblycera), and sometimes 

 differ in the two sexes of the same species. When this 

 is the case they are the antennae of the male which depart 

 from the typical condition, showing appendages on one or 

 more segments, probably used for grasping the female. 

 The antennae arise from or near the lateral margins of the 

 head, and usually from about the middle of the margin. 

 The fossa may be deep or shallow ; its angles projecting 

 and acute or short and rounding; and the antennae may 

 project directly and always from the head ( suborder 

 Ischnocera) or they may lie concealed in excavations on 

 the under side of the head (suborder Amblycera). 



The eyes are simple and are located in the lateral mar- 

 gins of the hind-head not far behind the antennary fossae, 

 in a deep or shallow ocular emargination of the lateral 



