ANATOMY AND PHYSIOLOGY 



6 9 



Female Genitalia. In Neuroptera,Coleoptera,Lepidoptera 

 and Diptera the vagina simply opens to the exterior or else 

 with the anus into a common chamber, or cloaca. Often, as 

 in Cerambyx (Fig. 77) and Cecidomyia (Fig. 78) the attenu- 



FIG. 79- 



Ovipositor of Locusta. A, lateral aspect; B, ventral aspect; C, transverse section; 

 c, cerci; d, dorsal valve; i, inner valve; v, ventral valve. The numbers refer to 

 abdominal segments. After KOLBE and DEWITZ. 



ated distal segments of the abdomen serve the purpose of an 

 ovipositor; thus in Cecidomyiidse, the terminal segments, tele- 

 scoped into one another when not in use, form when extruded 

 a lash-like organ exceeding frequently the remainder of the 

 body in length. 



A true ovipositor occurs in Thysanura, Orthoptera, Odo- 

 nata, Hemiptera, Hymenoptera and some other orders of in- 

 sects. The ovipositor consists essentially of three pairs of 

 valves, or gonapophyses a dorsal, a ventral and an inner 

 pair. The two inner valves form a channel through which 

 the eggs are conveyed. In Locustidse (Fig. 79) the three 



