328 



PHYLUM ARTHROPODA. 



They are omnivorous in their diet, active in their habits, 

 hiding during the day and feeding at night. They are 

 ancient insects, for related forms occurred in Silurian ages ; 

 they are average types, neither very simple nor very highly 

 specialised. Their position is among the Orthoptera, in the 

 same order as locusts and grasshoppers. The hatched young 

 are like miniatures of the adults, except that wings are 

 absent. If there are wings, they appear at the last moult, 

 when the cockroach becomes sexually mature. 



FIG. 174. Ventral aspect of male cockroach with the wings extended 

 An imaginary median line has been inserted. 



A., antennae; E., eye; P.T., prothorax; W 1 , first pair of wings; 

 W 2 , second pair of wings; C., cercus; St., style; Co. t coxa; 

 TV., trochanter ; f., femur ; 7Y., tibia; Ta., tarsus. 



