364 SYNOPSIS OF CANADIAN ARCTIADAE. 
Primaries glossy white, semi-transparent; with the costal edge, 
sub-costal vein, and space between, yellow; paler towards apex. 
Secondaries wholly white, semi-transparent. 
Under surface same as upper, but paler, with the discal cell on 
primaries partly dusky. 
Abdomen rather slender, whitish annulated with yellow, with a 
dorsal and double lateral rows of black dots. Anterior femora pale 
yellow ; feet rather long and slender, brownish. Hind tibie with 
the two pairs of spurs long. 
Length of body 5 lines. Wings expand 14 lines. 
Larva undescribed. 
“Hab.—London, rare; Mississippi. 
S. Isabella !—Abb. and Sm. 
Palpi brown, short, and hairy. Antenne filiform whitish above, 
brownish-yellow below. Thorax yellowish-brown, anterior portion 
darker. 
Primaries fulvous or brownish-ochreous, sometimes tinged with 
red ; with a discal spot, and an indistinct sub-terminal line of spots | 
along the outer margin, black. 
Secondaries yellowish-ochreous with a roseate tinge, semi-trans- 
parent; with two black discal spots, and several more of the same 
hue along the hinder margin. 
Under surface of primaries rosy, margined with ochre-yellow, and 
‘with a short black stripe on sub-median vein near base ; secondaries 
similar in color to the upper surface, with discal spots on both larger 
and deeper in color. , 
Abdomen ochre-yellow, with a reddish tinge, and three rows of 
black spots. Anterior thighs crimson in front ; legs black. 
Length of body 7-8 lines. Wings expand 14-16 lines. _ 
Larva. Head black and shining; body brownish-black, with 
irregular transverse rows of tubercles, from which arise tufts 
of stiff hairs, which are dull yellowish-red along the middle of the 
body and black towards each end. Under side lighter in color than 
upper. This larva, which is one of our commonest species, completes 
its growth in the autumn, and hybernates through the winter. In 
spring they usually feed for a few days before going into chrysalis ; 
they will eat almost any herbaceous plant. Length, about one and a 
half inches. 
