LYCNID. PIVHECOPS. 49 
median nervule emitted some little distance before the lower end of the cell ; submedian nervure 
sinuous, following the shape of the inner margin. H1INDWING, elongated, oval; costa 
very straight, outer and abdominal margins sweeping round in an even curve ; costal 
nervure not much arched at base, then straight, reaching the apex of the wing ; first subcostal 
nervule emitted far before the apex of the cell; fer disco-cellular nervule short, outwardly 
oblique, straight, /ower disco-cellular longer, upright, concave ; second median nervule emitted 
some short distance before the lower end of the cell. Asfenne with a well-formed, spatulate 
club. Zyesnaked. Body long. 
Pithecops contains but two described species in the Indian region, one of which 
(P. hylax, Fabricius) occurs in Sikkim, the Chittagong Hill Tracts, Sandoway, Arakan, 
Bassein, Burma, Province Wellesley, Perak, Nias Island, Sumatra, Java, Borneo, and Celebes. 
Its coloration is brownish-black on the upperside. The other species, P. fulgens, 
Doherty, has been found in Upper Assam only ; the male has a patch of brilliant iridescent 
blue on each wing on the disc and base above; the female is coloured like P. Aylax. Both 
_ sexes of P, hylax and the female of P. fulgens are very similar in appearance to Meofithecops 
zalmora, Butler, but an examination of their structure shews that they differ considerably in the 
shape of the forewing, and also in neuration, from any species of that genus. The underside 
of both species of Pithecops is white, the forewing with two small brown spots on the middle of 
the costa, and some brown and black marginal markings ; the hindwing with a very large round 
black spot at the apex, marginal markings as in the forewing. The transformations of P. 
hylax are described under that species. Herr J. Rober (Iris, vol. i, p. 61, pl. iv, fig. 26 (1886) 
appears to have described a new species of Pithecops from Eastern Celebes under the name of 
Plebeius phonix ; it is figured in Dr. Staudinger’s ‘‘ Exotische Schmetterlinge.” These are all 
the species known to me of the genus, which appears to be strictly confined to the Indo-Malayan 
region. I am unable to identify the “ Polyommatus” hylax, figured in Donovan's “ Insects of 
India,” pl. xlvi., fig. 2, and referred by Kirby in his ‘* Synonymic Catalogue,” p. 346 (1871) to 
this genus as Pithecops donovani. 
Key to the Indian species of Pithecops. 
A. Both sexes, upperside, both wings deep blackish-brown. 
639. P. uyLax, Sikkim, Burma, Malay Peninsula and Archipelago. 
B. Male, upperside, both wings with the disc resplendent cyaneous-blue ; female, upperside, both wings 
blackish. 
640. P. FULGENS, Upper Assam. 
639. Pithecops hylax, Fabricius. (PLATE XXVI, Fic. 161.) 
Papilio hylax, Fabricius, Syst. Ent., p. 526, n. 351 (1775) ; idem, id., Sp. Ins., vol. ii, p. 124, n. 559 (1781); 
idem, id., Mant. Ins., vol. ii, p. 77, n. 709 (1787); Hesperia Rurales hylax, id., Ent. Syst., vol, ili, pt. 1, 
P. 304, n. 152 (1793) ; Polyommatus hylax, Godart, Enc. Méth., vol. ix, p- 701, n. 244 (1823); Prthecops hylax, 
Horsfield, Cat. Lep. E. I. C., p. 66, n. 1, pl. i, figs. 2, 20, tage ; 2b, pupa (1828); id., Moore, Proc. Zool. 
Soc. Lond., 1865; p. 771; id., Butler, Cat. Fab. Lep, B. M.,, p. 161, n. 1 (1869) ; id., de Nicéville, Journ A. S. B., 
vol. li, pt. 2, p. 61, n. 167 (1882); Lycena hylax, Hopffer, Stett. Ent. Zeit., vol. xxxv, p. 27, n. 50 (1874) ; id., 
Staudinger, Ex. Schmett., p. 271, pl. xciv, male (1888). 
Hasitat : Sikkim, Chittagong Hill Tracts, Sandoway, Arakan, Bassein, Burma, 
Province Wellesley, Perak, Nias Island, Sumatra, Java, Borneo, Celebes. 
EXxPANSE: & 9, °95 to 1'1 inches. 
DESCRIPTION: ‘*MALE. UPPERSIDE, Joth wings deep blackish-brown, the colour 
being uniformly spread over the whole surface to the border of the hindwing which is silvery- 
white. [Forewing with an oval patch of paler brown on the middle of the disc.] A very 
delicate gray cilia interrupted with brown bounds the forewing. UNDERSIDE, both wings 
white with a greyish-silvery gloss inclining to blue, and the scales covering their surface 
large and rough ; sometimes beyond the disc both wings are traversed by a delicate, undulated, 
interrupted striga of reddish-brown, exterior of this by a broader continued fascia of the 
same colour, undulated at its outer edge; next follows an interrupted series of oblong 
[black] spots, and finally a regular narrow marginal line of intense black, exterior to which the 
f) 
