xxii LLOYD'S NATURAL HISTORY. 



accommodates itself to the various curves and inflections which 

 the insect is continually giving to it, and which are rendered 

 necessary from the manner in which it obtains its food. Most 

 of the caterpillars that produce day-flying Lepidoptera have 

 sixteen legs, which are of two distinct kinds. Six of them are 

 placed on the three anterior segments that portion of the 

 body which corresponds to the thorax of the winged insect and 

 the others are attached to the sixth, seventh, eighth, ninth, and 

 anal segments. The form of the anterior, or thoracic, legs is 

 wholly unlike that of the others, and they seem to be the prin- 

 cipal instruments of locomotion. They are of a horny sub- 

 stance, wide at the body and gradually growing narrower to the 

 lower extremity, where they terminate in a strong claw. Each 

 of them is divided into several segments, which correspond to 

 the different parts that compose the leg of the Butterfly (Plate 

 II., fig. i, represents a pair of these legs). The other legs, at- 

 tached to the hinder or abdominal portion of the body, are soft 

 and fleshy, and therefore have been called the membranous 

 legs or pro-legs. Their principal use is to support the body by 

 adhering to the slender twigs and shoots which the animals fre- 

 quent to procure their food. For this purpose they can be 

 lengthened and shortened at pleasure, and can even be drawn 

 almost within the body, like the horns of a snail. Their general 

 figure approaches to that of a truncated cone, which is termi- 

 nated by a fleshy foot, of a construction peculiarly fitted to cling 

 to a smooth surface or embrace a slender twig. What may be 

 called the sole of the foot expands into a somewhat triangular 

 plate, which is furnished on its inner edge with a row of small 

 horny peaks or claws, consisting of a short and long one alter- 

 nately, forming, as Reaumur remarks, a kind of palisade round 

 part of the circumference. When the disc or ventral plate of 

 the foot is dilated, these claws are turned outwards, and their 

 small curved points find inequalities to which they can adhere, 



