CATOCALA. T4T 



the spots increase, and the colour approaches a light grey. 

 Up to this time it consumes the cast-off skin, with the 

 exception of the horny covering of the head. ^\fter the fifth 

 moult the larva becomes darker, and it grows rapidly. This 

 time it does not generally eat the cast skin, and looks for other 

 food at once, though some specimens will consume the slough. 



The sixth moult is the last, when the full-grown larva is ' 

 about three inches in length, and rather slender in proportion. 

 It varies considerably in colour, and is sometimes uniform 

 ashy-grey, and sometimes nearly white, or varied with darker. 

 Some specimens are light flesh colour, and others are pale 

 brown. The whole of the surface is covered with distinct 

 black atoms, but there are no other markings. On the back 

 of the ninth segment is a small hump, which is black in dark 

 specimens, and generally dark blue in the paler ones, this 

 colour disappearing on the sides. Near this spot the colour is 

 paler, and is sometimes suffused with bluish. The sides have 

 white fleshy fringes. The head is large in proportion to the 

 slender anterior segments ; it is flat in front, yellowish, with a 

 dark brown border, and a slight notch above. The belly is 

 either white or bluish, with dark blue or brown spots. The 

 front pair of pro-legs is much shorter than the others, which 

 gives the larva a somewhat looping gait. 



Like other larvae of the genus, the larva of this species is very 

 active, and if touched will lash about like a stranded fish. It 

 rests by day, in chinks of bark, or on a stout branch, and 

 feeds at night. Between the end of July and the middle of 

 August it prepares a large loose cocoon of strong threads 

 between leaves or in a wide chink of the bark, and, after a 

 week, it changes to a large, slender, plum-coloured pupa, with a 

 blue bloom like a plum. The moth appears after three weeks, 

 usually at night. By day it rests on trees and fences, but is 

 very shy and difficult to catch. 



