76 The Form of Insects 



union. These can be discharged into the genital 

 pouch, where they fertihse the eggs, as these are dis- 

 charged from the vagina. 



Ovipositor. — Within the genital pouch of the 

 female Cockroach are three pairs of processes which 

 act as forceps for grasping the egg-capsule. One 

 pair belongs to the eighth segment, being attached 

 to the eighth sternite below, and to both eighth 

 and ninth tergites above. These processes (^anterior 

 gonapophyses) are broad and flat at the base, becoming 

 slender and bent with somewhat hooked tips. The 

 other two pairs {posterior gonapophyses) belong to the 

 ninth segment ; there is a large outer pair formed 

 by lengthened processes of the sternite itself, and a 

 small, harder inner pair (fig. 52). These two pairs 

 are situated above the anterior pair, in conjunction 

 with which they form a forceps working vertically. 

 They hold the capsule while it is being formed and 

 filled with eggs, and the impression made on it, 

 while still soft, by the inner hind pair, is to be 

 recognised in its toothed upper edge (fig. 53) (l, 51)' 



The cockroach's ovipositor is retracted within the 

 abdomen; in many insects, Moths and some Beetles 

 for example, which simply pass out their eggs on 

 to a leaf, its parts are little developed or altogether 

 wanting. In other insects it projects far out beyond 

 the abdomen ; its hind inner pair of processes being 

 modified into organs for piercing or cutting substances 

 in which the eggs may be laid, while the forward 

 pair and the hind outer pair form a sheath through 

 which the eggs are passed down. In the long-horned 

 Grasshoppers the ovipositor is sometimes as long as 

 the body ; by means of it the female lays her eggs 

 deep in the ground. In Cicads the inner processes 

 are modified into hard blades with toothed edges ; 

 these are moved backwards and forwards guided by 



