NEW NORTH-EASTERN SUMATRA BUTTERFLIES. 43 
median interspace, beg there curved inwards towards the base of the 
wing ; a very indistinct pale marginal line. Hindwing with a broad, out- 
wardly-blue-edged, discal white band, commencing broadly at the costal 
nervure, increasing in width to the submedian nervare, where it terminates; a 
prominent but narrow submarginal band, divided into spots by the veins, 
eradually increasing in width from the costa to the submedien nervure, where 
it ends; a pale indistinct marginal line. UNDERSIDE, both wings reddish- 
brown, all the white markings more prominent than above, and tinted with 
shining bluish. Forewing has the three subapical spots joined to the submar- 
ginal line ; an oval black spot in the submedian interspace, placed internally at 
the base of the first median nervule ; a diffused blackish spot in the same 
interspace between the large discal white spot and the submarginal line. 
Hindwing with an. additional curved basal white streak, placed anterior to the 
costal nervure; the abdominal margin broadly metallic greenish. Cita of 
both wings black, bearing a white dot in the middle of each interspace. A ddo- 
men at the base above with a broad bluish-white band. 
Nearest to A. nivifera, Butler, from Nepal and Assam (sic, Butler), the Malay 
Peninsula, Sumatra, Nias, and Borneo, Differs from Straits and Sumatran 
Specimens in having the discoidal streak of the forewing narrower and much 
shorter, the three subapical spots half as wide, the two posterior of the discal 
spots narrower, thereby all combining to make the black ground-colour of the 
wing of considerably greater extent. In the hindwing the discal band is broader, 
and instead of ending anteriorly in a small round spot, it is continued uninter- 
ruptedly and widely to the costal nervure. ‘The first subcostal nervule of the 
hindwing on the upperside is black not prominently snow-white as it is in 
A, nivifera. On the underside of both wings the ground-colour is reddish-brown 
or castaneous, not hair-brown ; in the forewing the discoidal streak is longer 
and quite undivided; there are no black streaks placed on the ground-colour 
between the veins, on the hindwing the discal band is wider, especially so at 
each end, and the series of rounded blackish spots between the discal and sub- 
marginal bands in A, assa is larger, more diffused, and deep castaneous instead 
of blackish. I have not seen A. nefte, Cramer, from Java, but that species is 
probably distinct from A, assa to judge from Mr. Moore’s figures of it in Proc, 
Zool, Soc. Lond., 1858, p. 13, n. 7, pl. 1, fig. 5, male and female. A. reta, 
Moore, from Sumatra, is another closely allied species, but differs apparently 
from A. assa in the forewing in having the terminal spot well separated from 
the rest of the discoidal streak, in the presence of an additional spot in the 
second median interspace, and in the hindwing in having the discal band 
widest on the costa, narrowest on the abdominal margin, while in A, assa the 
reverse is the case, 
Described from two male specimens in my collection, 
