COCKROACHES, ETC. 117 



eggs hatch out. Other species form a horny egg-case 

 which, however, is always retained within the brood- 

 pouch of the mother and the young are born alive. 

 In yet other viviparous species no egg-case is formed 

 at all, but the eggs, enclosed in a thin transparent 

 membrane, develop within a large brood-pouch. 



Viviparous Cockroaches are by no means uncommon ; 

 in fact, I am inclined to believe that almost half of the 

 known species bring forth their young alive. The 

 eggs and embryos of the viviparous species are of 

 course protected from the attacks of the Evania, but 

 on the other hand the death of a pregnant mother 

 results in the death of all her offspring, and, since 

 Cockroaches have many enemies, we cannot be certain 

 whether the viviparous habit or the ootheca-forming 

 habit is the more efficient in securing the safety of 

 the developing young. All the species belonging to 

 the sub-family Epilamprince are viviparous, and in 

 Sarawak I once captured a female of a species belong- 

 ing to this sub-family, Pseudophoraspis nebulosa, with 

 the under-side of her body covered with newly hatched 

 young ones clinging to it. I have no doubt that the 

 young were born alive and then swarmed on to their 

 mother. Their appearance was different from hers, for 

 they were clothed with fine hairs on the margins of 

 their bodies, and the thoracic shields were pitted or 

 punctate. A Ceylon species of Epilamprine, Phlebono- 

 tus pallens, has been found with the young running 

 about on the upper side of the abdomen of the mother 

 and covered over by the tegmina, or wing-covers. In 

 this species the wings of the female sex are much 

 reduced in size, so that the insect cannot fly. Never- 

 theless the wing-covers are large and arched, and as 



