22 STRUCTURE OF THE LEPIDOPTERA 



CHAPTEE III 

 THE LARVA 



IN almost every case the young caterpillar, oil quitting the ' shell ' 

 of the egg, finds itself standing on and surrounded by its natural 

 food, and immediately commences to do justice to the abundant 

 supply. It will either nibble away at the surface of the leaf, removing 

 the soft cellular substance, so that the leaf exhibits a number of 

 semi-transparent patches when held up to the light, or it will 

 make straight for the edge, and, closing its hori- 

 zontal jaws on either, side, bite the leaf completely 

 through, and thus remove a small piece each time. 

 Several naturalists have amused themselves by 

 performing experiments and making calculations 

 on the efficiency of the masticating and digesting 

 powers of the caterpillar. The illustrious Keaumur, 

 for example, proved that some of the cabbage 

 eaters disposed of more than twice their own 

 weight of food in twenty-four hours, during which 

 time their weight increased one-tenth. Let us see 

 what this would be equivalent to in human beings : 

 FIG. 14. THE A man weighing eleven stone would devour over 

 CATERPILLAR OF three hundred pounds of food in a day, and at the 

 THE CLOUDED d of that d h aboufc fifteen pounds mor 



YELLOW BUT- t . . * . . 



TERFLY than he did at the beginning ! 



So the young caterpillar eats, and rests, and 



grows, till, while still young, its body has become too large for the 

 already tightened skin. It evidently feels very uncomfortable. Its 

 appetite fails, and it remains for a time perfectly quiet in one spot, 

 having previously spun a little carpet of silk to form a firm foot- 

 hold during its temporary indisposition. Its colours have also 

 become dingy, and anyone, not understanding the character of its 



