DEILEPHILA TITHYMALI.
Plate IV.—Fig. 4.
This beautiful moth is peculiar to the Canary Islands, although allied species are found over the greater part of Europe.[6] It expands from three to three and a half inches. The fore-wings are silvery grey in colour, having dark olive-grey markings, and a long stripe of this colour, increasing in width towards the body, from the apex to the base. The hind-wings are a rich pink, having a marginal band of dark brown, and a fine white line on the outer edge. The antennæ, which are white, are thick and feathered. The head and body, thickly feathered with white, are of an olive brown colour. Two bands of black cross the top of the abdomen, which tapers off to a point, with bands of alternate white and olive brown slightly marked with black. The caterpillar is easily found on the Euphorbia where it feeds gregariously. It is a beautiful dark pink, the horn being of this colour. The dark pink is interspersed with dusky green and greyish black spots, and the caterpillar, when at full size, attains a length of about four inches. It is found from January till the end of May, but in the greatest numbers in April, whilst the Euphorbia is in its prime. The road-side between Rambla and Icod is a particularly favoured spot. About one or two inches of dried earth prepared as already mentioned are required for the larva to make its slight case in, though when in a natural state it buries itself much deeper, and the pupa is difficult to find. Some were fed and reared on a species of milk-wort. They thrived, but eventually turned into small moths of a paler colour than usual. The pupa varies much in the time of turning to the moth stage, according to the weather,—from six weeks, the usual time, to three months. Some caterpillars obtained in January did not become moths till the end of March; others taken at full growth on March 15th effected their last change to the moth during the last week in April and first week in May. The pupa when it first turns is of a beautiful shaded green colour with yellowish markings, but it changes to a uniform brown in a few days. The caterpillar is sometimes affected by a disease which consists of a small red fungus growing on the body, generally towards the tail. One small brood was entirely lost from this disease, which seemed to be contagious. As a rule, however, the larvæ are easy to keep, and the chrysalides hatch well and strongly. When numbers are kept, an old wine-case should be substituted for the smaller breeding-cages already mentioned, the mosquito-netting being used in the same way. A little sun is beneficial to them every day in the morning. When kept too long in the sun, however, they cease to feed, although when in a natural state sunny localities are most favoured. They are not night-feeders only.
[6]See [Appendix D.]