622 MR. A. G. BUTLER ON SPHINGID. [ Noy. 16, 
about half the width, abruptly failing just before anal angle, ovter 
margin not undulated; body greyish, markings obsolete: expanse 
of wings 1 inch 7 lines. 
N.W. India. Type, coll. F. Moore. 
Genus Percesa, Walker. 
1. PERGESA MONGOLIANA, N. sp. 
Like a small example of P. velata from Darjeeling, but ‘differing 
as follows :—central band of primaries above much less defined, more 
oblique, touching the inner margin at external angle, only black at its 
lower extremity ; remainder of the wing decidedly darker, so as to 
obscure the markings ; discal area pale towards the apex and (in two 
diffused spots) between first and second median interspaces ; secon- 
daries with the pale streak sharply defined at anal angle, where it 
forms a distinct, triangular, ochraceous spot ; eyes and tegule clearly 
bordered with white; sides of coxee and venter dull rose-colour : 
primaries below with outer brown border wider, paler areas red, a 
yellow patch towards apex, and a diffused yellow spot on second 
median interspace ; secondaries red, greyish on interno-median area, 
costa tinted with yellowish: expanse of wings 2 inches 2 lines. 
Nankow Pass, between Mongolia and China (Swinhoe). 
Type, B.M. 
The following is a description of the metamorphoses, from draw- 
ings made by a native Japanese artist under the superintendence of 
Mr. George Lewis :-— 
Larva. Whity brown at the sides, becoming gradually sandy brown 
towards the dorsal region, which is of a still deeper tint; the sixth 
and succeeding segments reticulated with dark brown ; anterior por- 
tion of dorsal region on. each of these segments obliquely blackish, 
quite black in front of the horn, which is normal in shape and tes- 
taceous ; auterior segments slightly deeper in colour, with two lateral 
longitudinal lines, the inferior one indistinct and brown, the superior 
one black and terminating on the fifth segment in a large bipupillated 
black ocellus with yellowish iris and black margin; a subdorsal 
blackish litura on the anterior segments ; head, venter, and claspers 
greyish brown, spotted with whitish ; the feet black ; thoracic legs 
testaceous: length 3 inches 1 line. 
Pupa. Whity brown, clouded with grey, and mottled with whitish 
below (particularly in front) ; anterior portion of segments reddish ; 
a lateral longitudinal series of black spiracular spots, with whitish 
borders: length 1 inch 5 lines. 
The larva feeds upon balsam. 
P. mongoliana appears to be not uncommon in Japan, and pro- 
bably occurs also in China; the larva is not unlike the darker form 
of Cherocampa lewisii. 
Genus CozrocampPa, Duponchel. 
1, CHEHROCAMPA PRUNOSA, 0. sp. 
Nearly allied to C. rosina, the wings longer and narrower, altogether 
