CASSIDARLE ; CI1RYSOMELINJ3. 



135 





rounded by a margin, which is formed by a prolongation from 

 the thorax and elytra, and which even conceals the head ; and 

 they are able to lie so close upon the surface of the leaves, that 

 no part of the body or limbs is visible. Their colours are mucli 

 varied, and often very prettily arranged in spots, points, rays, 

 c. The commonest species in this country is the Cassida mri- 

 dis, which is no more than 1-1 6th of an inch long, of a green 

 colour, with black thighs. Its larva, which lives on thistles 



and artichokes, has a 

 very flat body, with 

 spines set on the edges; 

 and it has the singu- 

 lar habit of covering 

 itself with its own ex- 

 crement, which it at- 



Fio. 358. CASSIDA VIRIDIS, IN ITS DIFFERENT STATES ; tacllCS in a mass toge- 

 a, larva ; 6, the same on a leaf, with its covering of .1 j 



excrement; c, pupa ; d, perfect insect. tiier > and carries OH a 



sort of fork, arising 



from its tail. The pupa, also, is very flat, with thin-toothed 

 appendages at the sides of the body ; and its thorax is broad, and 

 prolonged forwards in a rounded expansion, which covers the head. 

 660. In the sub-family Chrysomelince, or Golden Beetles, this 

 expansion of the thorax is generally wanting; the body is 

 usually of a hemispheric or ovate form, the base of the thorax 

 being as broad as the front edge of the elytra ; and the surface is 

 usually bespangled with the most brilliant hues, in which blue, 

 green, and gold, are pre-eminently conspicuous. Their motions 

 are generally slow, and many of them are destitute of wings. Of 



the genus Chrysomela, the 

 C. populi is one of the com- 

 monest British species ; it 

 is of a blue-black colour, and 

 has red elytra, tipped with 

 black ; and it is found upon 

 the willow and poplar, in 

 the larva as well as in the 

 perfect state. As in the 

 preceding group, the exuviae of the larvae are found collected into 



FIG. 359. CHRYSOMKLA POPULI ; a, Larva 

 l>, Pupa ; f , Imago. 



