i6 



ENTOMOLOGY 



sitic insects. Example, Ctenocephalus (Fig. 30). One hundred and fifty 

 species. 



17. Hymenoptera. Metamorphosis indirect. Mouth parts at the 

 same time mandibulate and suctorial. Prothorax usually small. Wings 



FIG. 28. Hydrophilns triangnlaris. Natural size. 



four, similar, membranous, transparent, with a few irregular veins and 

 cells; hind pair the smaller. Females with an ovipositor, modified for 

 sawing, boring or stinging. Larvae cruciform, mandibulate, caterpillar- 



j\ 



FIG. 29. Tipitla. A, larva; B, cast pupal skin; C, imago. Slightly reduced. 



like, with head and legs, or else maggot-like and apodous. Twenty-five 

 or thirty thousand species. Two suborders. 



Suborder Terebrantia (Phytophaga, Sessiliventres). Abdomen 

 broadly attached to [the thorax. Ovipositor modified for boring, sawing 



