PHYSIOLOGY OF INSECTS. 125 



pair nearest to the head ; middle legs (mesopedes) ; 

 and hind legs (metapedes). 



452. The natural position of the legs in most 

 insects, when perfectly at rest, is for the fore and 

 middle legs to point forwards, the hind legs back- 

 wards : some beetles form an exception to this, the 

 fore legs alone pointing forwards. 



453. The legs are so nearly of uniform struc- 

 ture, 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. 



454. The hip (coxa) is a short and nearly 

 globular joint : it either moves with perfect free- 

 dom 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 (coxa liberd), in the second, fixed 

 (coxa fixa). 



455. The thigh (femur) 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 scapus) : 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 (femur). 



