THE SHORT-TAILED BLUE 
211 
butterfly for its eggs, while in central Europe the Bird's Foot 
Trefoil (Lotus cornicutatus) is the more usual food of the larvae. 
The eggs are laid singly, usually on the base of the leaf. 
The egg is very small, exactly the same in diameter as the egg 
of C. minima , i.e. 0*40 mm. It is a compressed spheroid in 
shape and of a clear pale greenish-blue colour. The whole 
surface is covered with white reticulations like frosted glass 
and of an irregular network pattern, which varies much in 
formation in different specimens. The upper surface of the 
egg is only very slightly sunken, almost flat. The young 
larva escapes from the egg by eating away the crown and 
part of the side of the shell. When first hatched, it is very 
active and crawls rapidly for such a small creature. The egg 
stage lasts six days. 
Larva.—The larva, when fully grown after the fourth 
moult, measures 9*50 mm. in length. It is of the usual onisci- 
form shape ; the back is arched and has a slight dorsal fur¬ 
row only, and slightly flattened sides. The whole surface is 
densely studded with short spinous bristles, each rising from 
a remarkably formed base, composed of a bulb-centred star. 
Numerous shining, whitish-green lenticles, set in black rings, 
more or less starred, are scattered over the surface. The 
honey-gland is on the tenth segment, being a small, elongated, 
transverse fissure, very similar in general structure to that of 
Maculinea avion. But although so like the gland of avion , 
I was unable to induce it to exude any liquid when touched ; 
it also appears less sensitive to irritation. Each side of the 
eleventh segment is a partly-retractile tubercle. The ground 
colour is pale green, and there is a darker green stripe down 
the back and a series of oblique side stripes of fainter green ; 
in some specimens the lateral ridge is tinged with pinkish- 
brown. The head is shining black and, while resting, is hid¬ 
den by the overlapping first segment. The hibernating larvae 
are pale pinkish-ochreous, striped with brown and rust-red. 
After the second moult, the larvae devoured the seeds of 
Medicago lupulina , eating through the capsule to feed on the 
seeds. During the last stage, I supplied the larvae with the 
blossoms of both White and Red Clover. One larva ate up 
all the petals of a red blossom in two days ; it appeared to 
be feeding continually both day and night. The larvae 
