144 LYCANIDA. NACADUBA. 
HapitaT: Sikkim, Bhutan, Assam, South India, Ceylon, Andaman and Nicobar Isles, 
Malay Peninsula, Borneo, Philippine Isles, Australia, 
EXPANSE: 6, 1'2 to 1°63; 2, 1°3 to 1°5 inches. 
DESCRIPTION: “MALE. UPPERSIDE, oth wings plumbeous-violascent. UNDERSIDE, 
both wings palely hoary-fuscous, with two macular cognate submarginal fasciz, fuscous circled 
with whitish (evanascent in the forewing). Forewing with a disco-cellular fasciole and a fascia 
beyond it, broken at the second median nervule. Hindwing with a basal fascia, a disco- 
cellular fasciole and a contiguous external chain-shaped bent fascia of the ground-colour, 
circled with fuscous and whitish, indistinct, with a large posterior black ocellus, inwardly 
circled with a narrow yellowish lunule, outwardly divided with a slender metallic arch set on a 
whitish anal striga, and a pair of minute anal spots of the same colour.” 
“Has more acute forewings than the allied Z.[=JV.] Zermus, Felder,’’ from Amboina. 
(Felder, 1. c. in Reise Novara). 
The type specimen was obtained on Pulo Milu, one of the Nicobar Isles, and the late Mr. 
de Roepstorff and Mr. Man have obtained it on Kamorta, Nankowri, and Great Nicobar. I 
have before me three males only from the Nicobars, one from each of the above-named islands, 
and they present considerable differences in the shade of purple on the upperside and in the 
prominence of the markings on the underside ; when male specimens from the Andamans, 
Ceylon, Ootacamund, Sikkim, Bhutan, Assam, and Burma are brought together, these 
differences are still more marked. The only conclusion I can come to is either that many 
slight local races have arisen, which perhaps may not be constant to locality, or that the 
differences observed may be due to seasonal causes. The females show as great variation as do 
the males ; three from Ceylon have the metallic blue area confined to a small patch on the disc 
of the forewing ; another from Ceylon has it fully one-third larger, while a third from the same 
locality has the upperside almost entirely blue, leaving a narrow black border only. If such 
marked differences extend to the species when inhabiting a small region like the Island of 
Ceylon, it is not much to be wondered at if as great differences manifest themselves when a 
much larger region is considered. In the Nilgiris a curious seasonal form of the male occurs ; 
it has the discal fascia of the forewing on the underside filled in anteriorly with blackish, and 
a large discal patch of the same colour on the hindwing. Mr. E, E. Green possesses a very 
similar female specimen taken in Ceylon. Mr. G. F. Hampson informs me that this form 
occurs in the Nilgiris in the rains, the common form appearing in the dry season; this 
form of differentiation between wet and dry season broods recalls that obtaining in 
Lampides @lianus, Fabricius ; indeed in general facies and style of markings on the under 
surface Lampides and Nacaduba have a strong superficial likeness. Elsewhere, however, I have 
not observed any similar seasonal variation in Vacaduba, 
I give below a very full description* of the commonest form of the species which occurs 
in the Andaman Isles, Cherrapunji and Sibsagar in Assam, and in Sikkim and Bhutan, 
* Nacaduba macrophthalma, Felder, Lampides confr, factolus, Wood-Mason and de Nicéville, Journ, 
A. S. B., vol. xlix, pt. 2, p. 230, n. 40 (1880). Hasiratr: South Andaman Isles, Cherrapunji, Sibsagar, Sikkim. 
ExpansE: Male, 12 to 1°4; female, 1°5 inches. DescripTion: ‘‘FRMALE. UppeRSIDE much as in ZL. 
=.) pactolus, Felder [from Amboina], differing in having the dark fuscous outer border of the /orew/ng 
spotless, and that of the Azvdwing very much less distinctly marked in the same manner ; no disco-cellular 
mark in either wing, and the whole upperside apparently more clouded with smoky fuscous scales. UNDERSIDE, 
both wings very pale fuscous, with a submarginal fascia composed of rhomboid spots, and a marginal one of 
narrow oval spots fuscous of a rather darker shade than the ground, both margined and connected together by 
whitish, the latter of them developed in the hindwing, in the interval between the first and second median 
nervules, into a conspicuous jet-black circular spot divided externally by a semi-circle of pale blue metallic 
scales and encircled internally by luteous-white, and into two minute ones, one on each side of the submedian 
nervure, internally covered with blue scales, #orewing with two small subcostal spots, a short disco-cellular 
fasciole, and a discal fascia strongly faulted at the second median nervule, so that the outer white margin of its 
posterior portion is in line with the inner white margin of its anterior portion, and the inner white margin of its 
posterior portion is in line with the disco-cellular nervules. Azndwing with a similar disco-cellular fasciole, and 
complexly faulted and contorted discal and _ basal fascia ; all the fasciz in all the wings margined on both sides 
with fuscous of a very slightly deeper tint than the ground and with whitish, MALk. UpprrsipE, both wings 
semi-translucent palish fuscous, with a light and tolerably brilliant amethystine lustre, edged with a darker rather 
broad anteciliary line. UNbERSIDE, doth wings much as in the female, but with the macular submarginal 
fuscous fasciz broader, and the analand subanal black spots of the Azndwing rather larger and conspicuously 
encircled with fulvous internally,”’ (Wood-Mason and de Nicéville, |, ¢.) 
