LYCANIDA. DACALANA. 335 
Figure 208 shews both sides of a male specimen from Ceylon, and figure 209 both sides 
of a female example from Bholahat, both in my collection. 
Genus 141.—DAC ALANA, Moore. 
Dacalana, Moore, Journ. A. S. B., vol. liii, pt. 2, p. 36 (1884) ; id., Distant, Rhop. Malay., p. 240 (1884). 
** MALE, FOREWING, comparatively more triangular than in typical Jolaus (2. helius, 
Fabricius, a West African species), the exterior margin being somewhat oblique, and the 
posterior margin shorter ; veration similar ; on the upperside of the typical species, between 
the median and submedian nervures, is a tuft of fine hairs covering a small glandular-scaled spot, 
and on the underside there is alsoa tuft of hairs onthe middle of the posterior margin. 
HINDWING, comparatively broader, being less produced hindward, the afex more convex, 
and the glandular subcostal spot less prominent. Type, D. vidura, Horsfield.” (Afore, 1. c.) 
With reference to this diagnosis, Mr. Distant remarks that Zo/aus helius, Fabricius, “ has 
four [¢.e., three, if the terminal portion of the subcostal nervure is not counted as an additional 
subcostal nervule] subcostal nervules, whilst the typical species of Dacalana possesses fivé 
[i.e., four] subcostal nervules.”” This I can partially confirm, as I possess a male of D. vidura 
Horsfield, from Western Java, which certainly possesses four subcostal nervules to the forewing, 
and it is from the lack of this additional nervule that I have separated off the genus 
Arrhenothrix which follows from Dacalana. 
Idonot consider it necessary to describe the venation of this genus in full, as the 
difference in the number and position of the subcostal nervules in it and in Arrhenothrix 
(which I have fully described) are the only points of difference between the two genera as far 
as I know. They are the only genera occurring in India which have a tuft of hairs in the male 
on the upperside of the forewing. 
Dacalana occurs in Burma, the Malay Peninsula, Nias Island, Sumatra, Java, Bantam, 
and Borneo. Two species only have hitherto been placed in the genus, both of which are de- 
scribed below. 
891. Dacalana burmana, Moore. 
D. burmana, Moore, Journ. A, S. B., vol. liii, pt. 2, p. 36 (1884). 
HapsiTaT : Moulmein. 
EXPANSE: $,1°5 inches. 
DeEscrIPTION: MALE. “ UPPERSIDE, oth wings differ from typical D. vidura, Horsfield, 
from Java, in its darker blue colour, UNDERSIDE, doth wings differ also in being brighter and 
of an ochreous-brown tint, the transverse white band is somewhat broader, the submarginal 
black line composed of short curved portions between the veins, and the whole series forms 
a more curved line in crossing each wing. Hindwing has the black subanal and lobe-spot 
slightly smaller, and the former is but very slightly surmounted with red.” (d/oure, 1. c.) 
I have not seen this species. On rediscovery it is very desirable that the number 
of subcostal nervules in the forewing possessed by it should be noted and recorded, as the 
species may belong to the allied genus Arrhenothrix. 
T give below a description D. vidura, Horsfield, the type and only other known species 
of the genus, which occurs in the Malay Peninsula and Archipelago.* 
__* Dacalana vidura, Horsfield. Amblypodia vidura, Horsfield, Cat. Lep. E. I. C., p. 113, n. 45 3 Thecla 
vidura,|. Cuiple is figs. 6, 6a, male (1829) ; Lolaus vidura, Hewitson, Ill. Diurn. Lep., p. 43, n. 10 (1865) 5 
id., Kheil, Rhop. Nias, p. 31, n. tor (1384) ; Dacalana vidura, Moore, Journ. A. S. B., vol. liii, pt. 2, 
p- 36 (1884) ; id., Distant, Rhop. Malay., p. 241,n.1, pl. xxi, fig. 27, male (1884). Habitat: Java (Hors- 
JSield) ; Sumatra (Hewitson) ; Nias Island (KheiZ) ; Borneo (Moore) ; Penang, Malacca, Singapore, Bantam 
(Distant). Expanse.: Male, 1°2 to 1’9 inches. Description: “ Mace, Uppersipe, doth wings bright 
azure with a snowy refulgence spread as a delicate white powder over the surface, while the gruund-colour 
assumes in a different aspect a pale sea-green cast. Forewing ornamented with a delicate white silky brush- 
like appendage, reflected and closely applied to a blackish spot on the middle of the disc ; the margins 
are black, gradually increasing in breadth to the tip, being separated by acurved boundary from the azure 
ground. Aindwing with the posterior border marked with a black thread extending to the anal appendage, 
which bears besides a black lunule ; the extreme.cé/é@ is gray ; in the exterior [costal] margin is a hemispherical 
