INTERNAL ORGANS. 79 



and their base to the walls of the head, especially 

 the posterior portion, which is quite crowded with 

 them ; these muscles serve to draw the jaws to- 

 gether ; and since most of a caterpillar's time is 

 spent in feeding, their monopoly of the head- 

 cavity is explained. In the body, the riband- 

 like character of the muscles is fully developed, 

 but the continuity of the ribands is constantly 

 broken, for no one muscle ever crosses more than 

 two contiguous segments ; generally they pass 

 from the hinder end of one to the hinder end of 

 the next ; this accounts for the vast number 

 counted by Lyonet, and is incident to the jointed 

 character of the body, which, as we have said, lies 

 at the very foundation of its structure. These mus- 

 cles may be divided into three classes longitu- 

 dinal, oblique, and transverse ; the longitudinal 

 bands are made up of short muscles, each a seg- 

 ment in length, lying end to end, so as to give the 

 effect of long ribands, extending the whole length 

 of the body ; there are several such bands, each 

 of considerable width, and they form the inner 

 wall of the body. Just beneath them lie the 

 oblique muscles, which always extend from the 

 hinder end of one segment to the hinder end of 

 the next, and are found mostly upon the sides. 

 The transverse muscles lie next the skin, are 

 mostly confined to the sides, and those of one 

 segment are entirely independent of those of any 



