144 FABRE'S BOOK OF INSECTS 



implement of the jaws should possess a solid support and 

 powerful machinery. The Capricorn larva strengthens its 

 chisels with a stout, black, horny armour that surrounds the 

 mouth; yet, apart from its skull and its equipment of tools, 

 this grub has a skin as fine as satin and as white as ivory. 

 This dead white is caused by a thick layer of grease, which 

 one would not expect a diet of wood to produce in the animal. 

 True, it has nothing to do, at every hour of the day and night, 

 but gnaw. The quantity of wood that passes into its stomach 

 makes up for the lack of nourishing qualities. 



The grub's legs can hardly be called legs at all ; they are 

 mere suggestions of the legs the full-grown insect will have 

 by and by. They are infinitesimal in size, and of no use 

 whatever for walking. They do not even touch the support- 

 ing surface, being kept off it by the plumpness of the chest. 

 The organs by means of which the animal progresses are some- 

 thing altogether different. 



The grub of the Rose-chafer, with the aid of the hairs and 

 pad-like projections upon its spine, manages to reverse the 

 usual method of walking, and to wriggle along on its back. 

 The grub of the Capricorn is even more ingenious : it moves 

 at the same time on its back and its stomach. To take the 

 place of its useless legs it has a walking apparatus almost like 

 feet, which appear, contrary to every rule, on the surface of 

 its back. 



On the middle part of its body, both above and below, there 

 is a row of seven four-sided pads, which the grub can either 

 expand or contract, making them stick out or lie flat at will. 

 It is by means of these pads that it walks. When it wishes 

 to move forwards it expands the hinder pads, those on the 

 back as well as those on the stomach, and contracts its front 

 pads. The swelling of the hind pads in the narrow gallery 

 fills up the space, and gives the grub something to push against. 

 At the same time the flattening of the front pads, by decreasing 

 the size of the grub, allows it to slip forward and take half a 

 step. Then, to complete the step, the hind-quarters must be 



