Larger Image
Pl. 31.
1, 2 Purple Emperor; 3 var. iole.
4, 5 White Admiral, var. nigrina.
Var. hutchinsoni, Robson, which has been renamed pallida and lutescens, differs from the typical form in having the ground colour much lighter and brighter on the upper side and ochreous on the under side. It is shown on Plate [35.] The outline of the wings of this form, which occurs in June and July, is said to be less jagged, and this may be so as a rule, but it certainly is not always the case. Possibly this is "The Pale Comma" of Petiver.
There are two broods of this species in the year, but the first or summer flight of butterflies seems to depend upon a favourable season, as also does the second or autumnal brood, at least as regards the number of butterflies representing it. The late butterflies hibernate and reappear in April, or even March, of the following year. It has been stated that all the specimens appearing in the spring are of the form with plain under sides.
From eggs laid between April 27 and May 6, Miss E. Hutchinson, writing in 1887, says caterpillars hatched between 5 and 11. They were "fed" on currant and nettle mixed, and were full grown from June 17th till the 23rd. The first butterfly emerged on June 26, and the last on July 3, and all were very fine and of the pale summer variety. Two of the insects paired on June 30, and the female commenced laying on July 1, and continued doing so till the 10th, when there were 120 ova. Unfortunately, a very cold spell of weather began on July 12, and more than half the eggs perished. The butterflies resulting from the remainder appeared during August, from the 17th to the 27th, but they would not pair, probably because, although they had emerged at an early date, they properly belonged to the autumnal flight.
In 1894 Mr. Frohawk reared 200 of these butterflies from 275 eggs laid by a female between April 17 and June 1 of that year. The caterpillars were supplied with nettle only. The first butterfly emerged on June 30, and the last on August 2. Of the whole number forty-one were of the light fulvous form, var. hutchinsoni, and all the others of the dark or typical form. With few exceptions, the light-coloured butterflies were the first to emerge, and the major portion of these during early July, and before any examples of the dark form had come out.
The egg is at first green in colour with ribs whiter, but changes before the caterpillar hatches out to yellowish. In confinement the female butterflies deposit their eggs singly or in chains of three or four; probably the latter is the usual method of laying the eggs under natural conditions.