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thorax bears, at the front corners of its tergum, a pair of 

 horny elytra or wing-covers (rudimentary in the female 

 of B. orientalis) ; the metathorax has a pair of wings (absent 

 in the female of B. orientalis}. Each thoracic segment 

 bears a pair of walking legs. 



The abdomen has ten segments ; the first one has a 

 reduced sternum ; and the tenth, which bears a pair of 

 tactile cerci, has the sternum modified into two podical 

 plates between which is the anus. In the male the sternum 

 of the ninth segment has a pair of styles. In the female 

 the eighth and ninth segments are telescoped within the 

 seventh, the sternum of which is produced backwards as 

 a, boat-shaped prolongation, and forms the floor of the 

 genital chamber in which the egg-capsule is made and 

 carried. 



The male genital aperture is below the anus, and is sur- 

 rounded by a set of chitinous processes (gonapophyses). 

 The female aperture is within the genital chamber ; and 

 Above it there are gonapophyses. On the sides of the body, 

 between the thoracic segments and upon the first eight 

 .abdominal segments, .are the paired respiratory openings 

 or stigmata. 



Give a Description of the Head and Mouth-parts of the 

 Cockroach. 



The head represents seven fused segments. The upper 

 .epicranium and the lower clypeus form the broad front 

 of the head. The sides, between the epicranium and the 

 genae or cheeks, are occupied by the large compound eyes. 

 The antennae are inserted on the front below the eyes. 

 At the inner side of each antenna there is a small white 

 oval patch, the fenestra. 



Hinged on to the lower edge of the clypeus is the plate- 

 like upper lip or labrum ; and behind it, at the sides of the 

 mouth, are the two stout mandibles or jaws with toothed 

 inner edges. Behind these are the two ist maxillae ; and 

 the two 2nd maxillae, which are fused together, form the 

 lower lip or labium. 



Each 1st maxilla consists of a basal piece bearing inner 

 .and outer branches. The basal piece has two joints, proxi- 



