102 



BRITISH BUTTERFLIES. 



vertical arrangement. The egg is uniformly green in colour, the 

 ribbing paler, somewhat transparent, glassy, almost silvery, in hue 

 [Tutt. Description made on May 26th, from egg laid May 23rd, 1898] . 

 Globose, flattened ; the micropylar area depressed, covered with a 

 reticulation of raised white lines ; the egg of a pale sea-green colour ; 

 diameter 0*027 to 0-028 of an inch. In none of my specimens could 

 I find the double white lines described by Hellins ; the reticulation 

 was in single lines throughout. [Filer, June 7th, 1898.] About 

 *75mm. in diameter, the shape of a flattened sphere ; finely reticulated, 

 green in colour (Le Grice). [Sich refers the description of the egg, 

 supposed to be that of Thestor ballus, Ent. Bee, xv., p. 122, to this 

 species. Compare with his description Ent. Bee, xviii., p. 239, also 

 Ent. Bee, xv., p. 119.] 



Habits of larva. — Chapman observes that the larva eats a largish 

 piece out of the top of the eggshell, but does not apparently try to eat 

 the eggshell, It travels steadily but slowly, spinning a silken ladder as 

 it goes, until it reaches an opening bud of thefoodplant (Calycotome), at 

 the time, or just before the time, when the calyx makes its curious split 

 for releasing the petals, and is about 4mm. to 6mm. long. It here 

 settles down and eats a hole through the calyx. In four days many 

 of the larvae have acquired the red back with white subdorsal lines. 

 In feeding, the larva buries the head, and often a segment or two of 

 the thorax, but, in no instance observed, did it burrow right into the 

 bud and disappear. So well protected is it, however, when very 

 young, that Chapman notes (in litt.) that, on April 21st, at Hyeres, 

 he found an empty eggshell on a twig of Calycotome, but could not 

 find the escaped larva, but that he brought home the twig, and, on 

 April 25th, he observed it, when it appeared to be about fullgrown in 

 its first instar. After the first moult, the larva continues to feed in 

 the same manner as before, i.e., it burrows with its head and front 

 segments into the side of a partially-opened flower. It appears some- 

 times to try to form a nest by fastening a few adjacent points — leaves, 

 etc. — together. This was particularly noticeable in a young larva 

 about to undergo its second moult, which had pulled a leaf or two 

 lightly together, forming thus a vague sort of nest, perhaps, however, 

 it meant little more than the moulting-carpet getting an attachment 

 to more than one leaf. The smallness and thinness of the head and 

 prothorax must, one feels, greatly facilitate the thrusting of its head 

 into the flowers when feeding. After the second moult it eats away 

 the flowers much more completely. Some larvas that Chapman had 

 reared on Calcyotome spinosus till after the second moult, at once took 

 to broom and gorse when placed upon them, eating the flowers, and 

 also the leaves of Erica tetrali.v, apparently with equal goodwill. 

 During the third instar it still eats flowers, but much more completely 

 than hitherto ; whilst, in the last instar, they ate the flowers of broom 

 voraciously, and grew very rapidly. Prideaux observes that eggs laid 

 on June 10th, 1891, on young shoots of gorse, hatched on June 18th, 

 and were fullfed by July 14th, the whole larval period lasting less 

 than a month. As soon as the larvae left the eggs they commenced to 

 eat the young undeveloped shoots of the gorse, and concealed them- 

 selves with the greatest ease, whilst, later, they attacked Lotus major, 

 L. corniculatus, and various kinds of clover, eating the leaves when 

 pushed, but preferring the blossoms. Hellins observes that some 



