190 THE BUTTERFLY VIVARIUM. 



overlapping of the skin in the last segments of the 

 body, which are generally bent over the back, serves 

 to complete the resemblance, being very similar to 

 the scale-like jointing of the lobster's tail. Like 

 the Caterpillar of the Puss-moth, the anal pro-legs 

 are absent, their position being occupied by two 

 horn-like appendages, the use of which is not known. 

 The long pectoral legs, however, are said to be 

 necessary to the larva in the formation of its some- 

 what peculiar cocoon, the texture of which is not 

 unlike that of tissue paper. It will be observed 

 that the first pair of these singular legs, next to 

 the head, are very slender, and to a certain extent 

 rudimental, the full development being confined to 

 the second and third pair. This formation,' how- 

 ever, disappears in the perfect Moth, in which the 

 six legs are equal. There is a curious analogy 

 with this arrangement in the legs of certain Butter- 

 flies, as in those of the genus Vanessa, described in 

 Cbapter VII. ; but in that instance it is the front 

 pah- of legs of the perfect insect that are rudi- 

 mental, while' in the Caterpillar state there is no 

 indication of such a peculiarity. 



The "Lobster" Caterpillar feeds on Fagus Syl- 

 vatica, the Common Beech, and also on other forest 

 trees, as Alder, Hazel, Sloe, etc. It is found in 



