ACIDALIA EMARGINATA. 131 
The eggs are oblong-oval, and when fresh are 
orange-colour, but before hatching change to purplish- 
red; this event took place the day following their 
arrival. 
The newly emerged larva is olive-green, with 
wainscot-brown head. Being supplied with Poly- 
gonum aviculare, they fed and grew slowly until 
hybernation, which portion of their existence ex- 
tended over a long period, as they ceased feeding in 
the autumn, and did not recommence until early in 
May following. By the middle of June they were 
full-grown, and may be described as follows: 
Length about three-quarters of an inch, and of 
average bulk in proportion; head about the same 
width as the second segment; it has the face rather 
flat, but the lobes rounded, and 1s notched on the 
crown. When viewed from above the body seems 
flat, but seen from the side the under surface is 
rounded; the ninth segment is the widest, and from 
it the rest gradually taper towards the head; the 
tenth, eleventh, twelfth, and thirteenth are of about 
equal width; all these overlap considerably, thus 
rendering the divisions very distinct; this overlapping, 
too, makes the skin at the side appear as a conspicu- 
ous lateral ridge. The skin is tough and has a rough 
appearance, owing to its being transversely ribbed 
throughout. 
The ground colour is dirty ochreous, in some speci- 
mens strongly suffused with a dingy smoke-colour; 
the head is of the same colour, and from it extends a 
pale dorsal line, this line being bordered on each side 
of the tenth to thirteenth segments with an irregular, 
broad, and very dark stripe; on segments two to five 
these stripes are paler and narrower, whilst on seg- 
ments six, seven, eight, and nine they become con- 
spicuous black X-hke marks; the side of the lateral 
ridges is tinged with reddish-ochreous, and there are 
various brown freckles between this and the dorsal 
line. ‘The ventral surface is of the same tint as the 
