2 7 6 



Hominoxious Arthropods 



dd. Eyes indistinct or wanting; pharynx long and slender, fulturae very 

 slender and closely applied to the pharynx; proboscis very long. 



Several genera found upon various mammals H^MATOPINID^E. 



cc. Body swollen; meso- and metathorax, and abdominal segments two to 

 eight each with a pair of stigmata; eyes wanting; antennae four or 

 five-segmented ; body covered with stout spines. Three genera found 



upon marine mammals ECHINOPHTHIRIID^E 



aa. Legs fitted for walking or jumping; spiracles of abdomen usually ventral; 



beak segmented. 



b. Apex of head usually directed anteriorly ; beak arising from its apex ; sides 

 of the face remote from the front coxae; first pair of wings when present 

 thickened at base, with thinner margins HETEROPTERA 



159. Taxonomic details of Hemiptera-Heteroptera. (a) Dorsal aspect ; (b) seta from 

 bedbug; (c) wing of Heteropteron; (d) leg; (e) wing of Sinea. 



c. Front tarsi of one segment, spade-form (palaeformes) ; beak short, at 

 most two-segmented; intermediate legs long, slender; posterior pair 



adapted for swimming CORIXID^; 



cc. Front tarsi rarely one-segmented, never spade-form; beak free, at least 



three-segmented, 

 d. Pulvilli wanting. 



e. Hemelytra usually with a distinct clavus (fig. 159), clavus always 

 ends behind the apex of the scutellum, forming the commissure. 

 (Species having the wings much reduced or wanting should be 

 sought for in both sections.) 



f. Antennas very short; meso- and metasternum composite; eyes 

 always present. 



