PIERIS CHEIRANTHI.
Plate I.—Fig. 2.
This is a large creamy-white butterfly peculiar to the Canary Islands. It is found in some numbers on and near the coast of Teneriffe from April to September; the time of its appearance, however, varies somewhat in different years. The larva is smooth, and has a ground-colour of grey, finely dotted over with black spots. There is a yellow stripe on the back and along each side. It feeds on the nasturtium gregariously, and the pupa attaches itself, head downwards, to a wall near the plant.
The female butterfly, the underside of which is illustrated, has a long uneven blotch of black on the surface of the fore-wings; the male has none. The upper surface of both sexes is cream-white, with a black apical patch on the fore-wings. The under-sides have the long black blotch as seen on the surface of the female, and the ground-colour of both is yellow, finely sprinkled with black dots. The measurement across the wings varies from two and a half to three and a half inches.
It is best to procure the larvæ to obtain good specimens, but the Ichneumon fly is such an enemy to this species that great disappointment will probably be experienced in the rearing if the caterpillars are not well examined before being placed in the breeding-cages.