416 MODERN CLASSIFICATIOM OF INSECTS. 



(the antennae being inserted in the notch on the inside) ; the ocelli 

 obsolete; the legs are long and compressed (^fig. 51. 9.), well formed 

 for running, the tibiae being armed with numerous strong, movable 

 spines, and with apical spurs ; and the tarsi of all the legs being 

 5-jointed, the basal joints not being furnished with cushions beneath 

 (as in crawling insects) ; the terminal ungues are strong, between 

 which there is a pulvillus ; the abdomen is furnished at the tip with 

 two short, conical, compressed, articulated appendages {^fig. 51. ll.), 

 which exist in both sexes ; besides which, in the males, there is 

 also a pair of slender, external; inarticulated appendages (sometimes 

 these are difficult to be observed ; so that M. Hummell denies their 

 existence in the males of B. germanica), as well as an elongated, 

 horny, intermediate one, which is recurved at the tip, and occasionally 

 retracted within the abdomen (^Jig. 51. 10. $ ). 



The males are distinguished by being smaller, and of a more slender 

 form, and having eight ventral abdominal segments ; whilst there are 

 only six or seven ventral segments in the females, the terminal segment 

 in the latter being occasionally keeled. In this sex the abdomen is much 

 broader and larger than in the males. The sexes also differ in the 

 developement of the wings. In B. orientalis the males have short 

 tegmina and wings, not covering more than two thirds of the ab- 

 domen ; whilst in the female the tegmina are very small, having a 

 wide space between them, not extending beyond the metathorax 

 (^fig. 51. 12.), and the wings entirely obsolete. BruUe says that De 

 Geer and Geoffroy have regarded the pupa of this species as the 

 mature female; but this is evidently an error, as the individuals 

 which these authors have figured as the female precisely agree with 

 the individuals which are to be found carrying their capsules of eggs 

 about with them, and in which there are no rudiments of posterior 

 wings. Do these females ever acquire larger rudimental wing-covers ? 



In Blatta nigripes, the males have fully developed tegmina and 

 wings ; but in the females the tegmina cover about half the abdomen, 

 slightly folding over each other ; but the wings are also wanting. In 

 B. lapponica, the male and female of which are well figured by De 

 Geer, 3. t. xxv. f. 9, 10., the tegmina and wings, both of the males 

 and females, are developed; but those of the latter do not quite cover 

 the larger abdomen. In B. germanica, the tegmina of the female cover 

 the abdomen, except at the sides, owing to its greater breadth. 



These insects were well known to the ancients, who named them 



