154 



BKITISH BUTTERFLIES. 



shape is also departed from, in that, above the marginal zone of the 

 egg, the side does not at once rise, but first falls in giving a sort of 

 circular groove or hollow just above it. But this departure from 

 the bun-shape has again to be partially or wholly explained away, 

 because the swollen zone round the margin which produces it, is not 

 altogether part of the egg itself, but chiefly, if not entirely, projecting 

 processes such as do not exist at a higher level. The inner dome- 

 shaped portion of the egg is smooth with regular scattered hairs. 

 These are about 0-014mm. long, shorter on top, disposed in hexagonal 

 alignment, and 03mm. apart. They are, in fact, all that appears of 

 the theoretically present hexagonal network, with knobs or spicules at 

 the angles ; these are the spicules. At the marginal protuberance 

 these change, practically suddenly, but with just enough transition to 

 show that it is so, into four or five rows of long yellow processes, which, 

 seen from above, seem part of the solid egg. They are about 0-03mm. in 

 length, and are expanded terminally into four conjoined knobs. In these 

 specimens these are (like the fine hairs) straw colour. They are too 

 long and too close together to permit the surface below to be well seen, 

 but there is, at any rate, a yellow raised line at least in the zonal 

 direction from one to the next. The undersurface appears to have 

 hairs something like the upper surface, but connected together by a 

 network of raised lines. The collapsed egg happens to afford evidence 

 that the hairs, etc., are not part of the egg proper, but form a super- 

 ficial layer, as in places it has scaled off, and, at the margin of the bare 

 places, this superficial portion is partially raised and loose. [Two eggs 

 received March 22nd, 1906, from Mr. Tutt, both unfortunately dead. 

 One of them a good deal collapsed. The other with a hole in the top, 

 through which a young larva, especially its true legs, can be seen, but 

 shrunk and dead, obviously after having made an attempt to emerge ; 

 both have black and pale portions, the result of where a black (or 

 black portion of a) larva underlies the shell or a pale portion of larva, 

 or a cavity exists.] (Chapman). Newman describes the egg as being 

 " shaped something like an orange, but more depressed on the crown " 

 (compare pi. ii., fig. 4, with this description, which evidently did not 

 belong to the species). 



Habits of larva. — The larva leaves the egg towards the end of 

 March, March 18th, 1907, at Eeigate (Chapman), March 20th, 1907, 

 at Berlin (McDunnough), having been quite fully-formed within, and 

 capable of existence outside, the egg for some weeks. It appears at once 

 to crawl between the flowering- buds, and seemingly lives there in its earli- 

 est stages, and this possibly explains the repeated mention, by different 

 observers, of the marked partiality of the larvre, in some places, for 

 branches bearing fruit. Bird observed a larva, May 21st, 1907, hiding 

 between two of the seed-vessels of wych-elm. Newman's remark that the 

 young larvae leave the egg in April and May appears to be largely guess- 

 work, for, certainly, in average seasons, May, and possibly the greater part 

 of April, is much too late a date. The larva at first grows slowly, and is 

 rarely noticed in nature until in its penultimate skin, when it usually 

 rests on the underside of a young leaf, and is somewhat difficult to 

 detect, even on the lower branches of elms that are well within the 

 range of vision. In confinement, in their first stadium, the larvae at once 

 commenced eating circular holes of considerable depth into elm-buds, 

 and, in order to moult, retired to the base of the bud, spinning a small 

 cushion of silk, to which they attached themselves very firmly 



