ITS NATURAL HISTORY. 



now passed one by one into the capsule ; and as it becomes full, 

 its length is gradually increased by fresh additions, while the 

 first-formed portion begins to protrude from the body of the 

 female. When sixteen eggs have descended, the capsule is 

 closed in front, and after an interval of seven or eight days, is 

 dropped in a warm and sheltered crevice. In Periplaneta 

 orient alls it measures about *45 in. by '25 in. (fig. 5). The ova 



Fig. 5. Egg-capsule of P. orientalis (magnified). A, external view ; 



B, opened ; C, end view. 



develop within the capsule, and when ready to escape are of 

 elongate-oval shape, resembling mummies in their wrappings. 

 Eight embryos in one row face eight others on the opposite side, 

 being alternated for close packing. Their ventral surfaces, 

 which are afterwards turned towards the ground, are opposed, 

 and their rounded dorsal surfaces are turned towards the wall of 

 capsule ; their heads are all directed towards the serrated edge. 

 The ripe embryos are said by Westwood to discharge a fluid 

 (saliva?) which softens the cement along the dorsal edge, and 

 enables them to escape from their prison. In Blatta germanica 

 the female is believed to help in the process of extrication.* 

 The larvae are at first white, with black eyes, but soon darken. 

 They run about with great activity, feeding upon any starchy 

 food which thev can find. 



%/ 



The larvae of the Cockroach hardly differ outwardly from the 

 adult, except in the absence of wings. The tenth tergum is 

 notched in both sexes, as in the adult female. The sub-anal 

 styles of the male are developed in the larva. 



Cornelius, in his Beitrage zur nahern Kenntniss von Peri- 

 planeta orientalis (1853), gives the following account of the moults 



* Hummel, loc. cit. 



