12 



ENTOMOLOGY 



FIG. 15. 





Oligotoma 



lichaeli. Length, 10.5 mm. After 



McLACHLAN. 



ments, and a pair of stout biarticulate cerci. Integument deli- 

 cate. Not social in habit. Examples, Embia, Oligotoma 

 (Fig. 15). Some twenty species, all from warm climates. 



These insects are most 

 nearly related to Termit- 

 idae and Psocidae. 



Psocida. Eyes facet- 

 ted. Antennae 13-50 

 jointed. Mouth parts 

 hypognathous. Protho- 

 rax reduced. Wings 

 present, rudimentary or 

 absent; front pair the 

 larger; veins few and ir- 

 regular. Abdomen with 

 nine or ten segments and 

 no cerci. Integument delicate. Example, Psocus (Fig. 16). 

 About two hundred species. 



Comstock raises Psocidse to the rank of an order, for which 

 he employs, in a new sense, Brauer's term Corrodentia. 



Suborder Mallophaga. Wingless flattened insects, of para- 

 sitic habit. Head large. Eyes consisting of a few isolated 

 ocelli or else absent. An- 

 tennae 3-5 jointed. Mouth 

 parts prognathous. Pro- 

 thorax distinct ; mesotho- 

 rax often and metathorax 

 usually transferred to the 

 abdominal region. Ab- 

 dominal segments eight to 

 ten in number ; no cerci. Parasitic upon birds and a few mam- 

 mals. Example, Menopon (Fig. 17). More than fifteen 

 hundred species have been described. 



Packard's order Platyptera originally included Perlidae. 

 Brauer's order Corrodentia consisted of Termitidae, Psocidae 

 and Mallophaga; Perlidae being set apart as an order (Plecop- 



FIG. 16. 



Psocus venosus. Length, 5 mm. 



