1895.] L. de Niceville & Dr. L. Martin — Butterflies of Sumatra. 487 
523. ^Delias egialea, Cramer. 
Wallace. Snellen. Staudinger. Kirby. A Javan species, which 
may perhaps occur at the south-eastern end of Sumatra. 
524. Delias tobahana, Rogenhofer. 
D. tobahana, Rogenhofer, Yerh. zool.-bot. Gesellsch. Wien, vol. xlii, p. 571, n. 1 
(1893); id., Mitis, Iris, vol. vi, p. 102, n. 13, pi. ii, fig. 1, female (end of January, 
1893). 
D. derceto, de Niceville, Journ. Bomb. Nat. Hist. Soc., vol. vii, p. 557, n. 12 
(23rd April, 1893); idem, id., 1. c., vol. viii, p. 52, n. 12, pi. L, fig. 4, male (1893). 
Rogenhofer. Hagen. Originally described by Herr Rogenhofer 
and I from Sumatra. Found only on the Central Plateau in the Toba 
and Karo districts, where it is by no means common, and strange to say, 
the males rarer than the females. Dr. Martin has specimens taken only 
in March, May, June, July, and September. It is of very delicate struc¬ 
ture, and seldom seen perfect. 
525. Delias belladonna, Fabricius. 
Pieris chrysorrhoea , Vollenlioven, Mon. Pierides, p. 6, n. 3, pi. ii, fig. 4, male 
(1865). 
Kirby as chrysorrhsea [sic]. I do not propose in this place to 
discuss the innumerable forms of this species which have been 
described and named, of which von Mitis enumerates seven “ varieties” 
besides the type, and has omitted two others, D. hearseyi and 1). boylese , 
both of Butler. To these names I have to add the “ Pieris ” chrysorrhoea 
of Vollenhoven, described from the mountains in the interior of 
Sumatra. This species does not appear to have ever been properly 
understood, even von Mitis in his recent Monograph of the genus 
does not put it in the same group as D. belladonna. The figure differs 
from our specimens of D. belladonna from the Battak mountains in 
having the white areas on the upperside of both wings, but especially 
of the hind wing, larger and more or less coalescing. The figure does 
not show the characteristic yellow spot at the base of the hindwing 
on the upperside owing to the way the specimen drawn was set, the 
costa of the hindwing being broadly covered over by the forewing. 
The non-perception of this spot is probably the cause that the species 
appears never to have been recognised until now, combined with the 
fact that D. belladonna in none of its forms was ever suspected to 
occur in the region of the equator. The vast stretch of country between 
Assam, the most southernly point hitherto known for D. belladonna , 
and Sumatra has however been partially bridged over by the discovery 
of the butterfly by Capt. E. Y. Watson in the Chin and Shan Hills of 
