OF THE LEGS. 169 



The legs are so nearly of uniform structure, that the 

 description of one serves for the six ; trifling variations, 

 where they occur, being easily pointed out in descriptions. 

 The legs of an insect consist of four parts, called the hip, 

 thigh, shank and foot. 



The hip or coxa, a 1, is a short often nearly globular joint : 

 it either moves with perfect freedom in a socket, purposely 

 excavated in the sternum of the insect, or is anchylosed 

 in the socket, and a greater power of motion possessed by 

 the next joint: in the first instance the coxa is called free 

 or coxa libera, and in the second, fixed or coxa Jixa. 



The thigh or femur, a 2, is a long and stout joint, 

 moving with great freedom ; it is composed of 

 three pieces, the separation of which is marked 

 by strong sutural lines: these are called the ^^' 

 first, second, and third joint of the femur, — 

 femoris caput; femoris trochanter ; femoris 

 scapiis: — when two parts only are discernible, 

 they are the second and third parts : when only 

 one, it is the third part, and is alone called the 

 thigh or femur. 



The shank or tiMa is a single piece, gene- a 5 

 rally of about equal length with the fetmir, but ^^s °^ ^ BeeUe. 

 occasionally differing greatly in this respect: it is fre- 

 quently three-sided. The tibia is called winged or alata 

 when it is furnished with an attenuated dilated process, 

 much resembling the extended membrane which consti- 

 tutes the wing of a bat, but not so flexible. It is called 

 corbiculate or corbiculata when it is furnished with a brush 

 of stout hairs, for the pui'pose of brushing the pollen fi'om 

 the anthers of flowers, and conveying it to the nest, as in 

 bees. The tibia in almost all insects is furnished with stiff 

 spines or bristles, which are called spurs or calcaria. 

 The foot or tarsus consists of five joints, called the 



