FAMILY ZYGiENID^. 19 



Larva. It is difficult to give even in general terms the 

 family characteristics of the larvge of the Lepidoptera, since there 

 are so many exceptional forms. In characterizing those of the 

 Zygaenidae we select that of the European Zygsena, and say 

 from the figures and descriptions of authors that they are short 

 and thick fleshy cylindrical larvas, whose bodies taper rapidly 

 towards either end. The head is very small and partially 

 retractile within the anterior part of the pro-thoracic ring. The 

 tip of the abdomen is likewise very small and more acute than 

 in the typical form of other families. The feet are sixteen in 

 number. The rings are convex, short, and with transverse rows 

 of unequal tubercles which give rise to thin fascicles of very 

 short evenly cut hairs, which are seldom dense enough to obscure 

 in the least degree the outlines of the body, and are often nearly 

 absent. Often there are one or two transverse^bands of gay 

 colors or of dark spots between the rows of tubercles and the 

 edges of each ring. The colors are greenish or yellowish. This 

 form is more especially that of the subfamily Zygseninae. 



When we depart from this typical form and ascend to the 

 neighborhood of Alypia and allies we find them elongated, with 

 large heads, and with a supra-anal tubercle towards which the 

 body imperceptibly increases in size : the colors are gay, and 

 the long unequal sparse hairs arise from minute tubercles. This 

 form is evidently influenced by the close approximation of the 

 genera to the Sphinges. This is the prevalent form of the 

 Castniares. On the other hand in descending towards the 

 Bombycidse, we find the larvae again elongating, but not by any 

 means so much so as in the Castniares, while the head still in- 

 creases in size, and the body is rather thickly clothed with hair, 

 with mesial tufts of larger and party-colored hairs. 



The larva of Ctenucha resembles the Arctians very remarka- 

 bly. Stoll* figures the larva of a genus which resembles closely 

 the larva of Halesidota, which is still longer than Arctia, being 

 related to Orgyia. It is elongated, very hairy, with long pen- 

 cils of party-colored hairs before and behind. The pupa is like 

 that of Arctia, while the moth belongs to the old genus Glau- 

 copis, having feathered antennas and a Sesia-like body. 



When the larva is about to pupate, it constructs a dense 

 silken cocoon generally, but Eudryas and Castnia make no 



^Supplement a POuvrage, intitule Les Papillons exotiques. Par M. Pierre 

 Cramer. PI. xi. fig. l,a, b, c, (J. 



