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MANUAL OF ELEMENT ARY ZOOLOGY 



are hidden. 1 The first sternum is rudimentary, and the 

 tenth tergum projects backwards as a plate with a deep 

 notch in its hinder edge. A pair of many-jointed, spindle- 

 shaped cerci anales, which may represent limbs, are attached 

 under this plate, and below it is the anus, between two 

 podical plates, which may represent the tergum of an 

 eleventh segment. In the female the seventh sternum is 



Fig. 181. — The ventral aspect of a male cockroach with the wings 

 extended. An imaginary median line has been inserted. — From 

 Thomson. 



A., Antennae; C, cercus ; Co., coxa, the breadth of which makes it look, in its 

 present position, like a ventral plate on the body ; £. , eye ; F. t femur ; P.T., 

 prothorax ; St., style ; To., tarsus ; 7Y., tibia ; 7V., trochanter ; U'X, first pair 

 of wings ; W 2 ., second pair of wings. 



produced backwards into a large boat-shaped process, 

 which forms the floor of a genital pouch, and in the male 

 the ninth sternum bears a pair of slender, unjointed styles. 

 The genital opening is placed below the anus and is 

 surrounded by a complicated set of processes known as 

 gonapophyses. 



The alimentary canal has long, ectodermal fore- and hind- 



1 In the male P. orientalis portions of the eighth and ninth terga 

 remain uncovered, 



