THE LIFE-HISTOKY OF OCNEUIA DISPAH. 239 



and are not easily worried. These remarks apply equally to the larvre 

 of Fsilnra monacha, to which species 0. disjicir is very closely allied in 

 every stage of its existence. 



Although the larvae are moderately hairy, I have not found that the 

 hairs possess any " urticating " j^roperties ; but the short bristly ones on 

 the back ax'e capable of giving a sharp prick when brought into contact 

 with the tender parts of the hand. 



The larva attains full growth in about eight weeks after leaving the 

 egg ; it is a rapid crawler and does not roll into a ring on the approach 

 of real or fancied danger. It spins a very rough, open network of silk 

 in some convenient corner, or between leaves, and therein becomes a 

 jiupa. This network in no way hides the enclosed pupa, but is only 

 just sufficient to restrain it from rolling about or falling out. 



The pujife of both sexes are of a dark brown colour, and are 

 besprinkled with little tufts of short hair of a lighter shade of brown. 

 The male pupa is only about half as large as that of the female ; it is 

 rather squarer at the head and decidedly more pointed towards the tail. 

 Both sexes rotate the tail segments very actively when touched. 



The moths appear in July and August, about a month after the 

 pupation of the larvee. 



In the early stages of this moth there is not a very striking 

 difference between the sexes ; but as soon as they arrive at the imago 

 stage they present very few points of similarity. The male differs very 

 materially from the female in size, colour and shape, as is evident on 

 the most cursory glance. The antennae of the male are beautifully 

 plumose ; those of the female pectinated. The fore- wings of the male 

 are of a rather greyish-brown colour (either shade occasionally 

 predominating) with darker transverse wavy lines ; the hind-wings are 

 always of a lighter brown than the fore- wings, and, as a rule, aj)pear to 

 be destitute of markings, with the exception of a central dark lunule : 

 there is, however, sometimes an indication of a line parallel with the hind 

 margin ; though this is rather more distinct in the female. The fringe is 

 alternately light and dark on all the wings. The female agrees with 

 the male in the style of the markings, but the ground colour of all the 

 wings is creamy-white. Both sexes have a blackish dot and a 

 V-shajDcd mark rather above the middle of the fore-wing. The 

 distinctness of the transverse lines varies in both sexes, but especially 

 in the female, and a variety of that sex occasionally occurs in wliich 

 the V-shaped mark alone is present. 



I am indebted to Mr. Samuel Stevens of Norwood for the loan of 

 2 males and 2 females of an original British race. You will notice 

 that the second male is a very strikingly banded variety ; otherwise 

 there is no particular individuality about our old fen form. 



You will see in my boxes a number of small males very mucli 

 lighter than usual, and having a good deal of buff colour on the fore 

 wings ; many of them also have the thorax greyish. They are the 

 produce of several generations, and were bred in the first instance from 

 ova received from Mr. Bacot, who got them from Mr. Wade-Gery of 

 Winchester College. 



It was by means of a score of larvae, which I ol»tained in 1886 

 from Mr. J. Potts of Hull, that I first made acquaintance with the 

 species ; and the acquaintance had ripened into friendshi}) with suc- 

 ceeding generations, when I unfortunately lost the race iu 1891. 



