Lepidoptera of Sikkim. 419 
386. Tachyris lalage. 
Pieris lalage, Doubl., Gen. Di. Lep., t. vi., fig. 5 
(1847). 
P. durvasa, Moore, P.Z.§8., 1857, p. 103, t. 44, 
ng. 6, dys 
Common at low elevations from April to October. The 
females, which are rarer than the males in their proper 
habitat, have the habit of flying up to great heights on 
the mountains. I took females of this species on Tonglo 
at 8500 ft., on the Rishilah in Bhutan at 10,400 ft., 
and in the Khasia hills at the highest peak on the 
Shillong plateau, 6400 ft.; but saw no males in any of 
these places. Why this very curious habit should be so 
marked in some species of purely tropical butterflies in 
Sikkim, I cannot say. It would seem to be a sort of 
instinct tending to decrease rather than increase the 
number of individuals of these species, as it is im- 
probable that these females could regain their natural 
breeding-places. I shall be curious to learn whether 
the same habit has been noticed in other mountainous 
parts of India. 
887. Tachyris indra. 
Pieris indra, Moore, P.Z.§., 1857, p. 103, t. 44, 
O70, Sis 
Tachyris indra, Wallace, Trans. Ent. Soc. Lond., 1867, 
p- 881, 3. 
The male is not uncommon at low elevations from 
April to October, but the female seems much rarer, and 
I have not seen more than two or three specimens in 
Moller’s collection. 
388. Hronia avatar. 
Eronia avatar, Moore, Cat. E.I.C., p. 61, t. 11a, 
£5) Pig 857). 
Common up to about 5000 ft. from April to November. 
389. Hronta hippia. 
Papilio hippia, Fab., Ent. Syst., i1., 1, p. 59 (1787). 
Ironia gea, Feld., Voy. Nov., i., p. 190 (1865). 
This species occurs in the Terai, and has been taken 
in the Tista valley in May, but is hardly to be called a 
hill insect. 
