308 



RHOPA LOCERA MALA YA NA . 



Genus DERCAS. 



Pnms, Boisdnval, in Doubl. Gen, Diurn. Lep. p. 70 (1847); Bull. Gist. Ent. vol. i. p. 45 (1670)- 



Anterior wings siibtriangiilar, the costal margin convex, the apex more or less dentate, the outer 

 margin oblique, the inner margin concavely sinuate. Costal nervure terminating on coata a little beyond 

 end of cell ; first subcostal nervule emitted at less than one-third before end of cell, second near end of 

 cell, third and fourth subcostal uervulerf bifurcating nearer end of cell than apex of wing, fifth emitted at 

 about two-thirds the distance between end of cell and bifurcation of third and fourth ; upper disco-cellular 

 nervule concave and a little less than one-half the length of lower, which is directed outwardly towards 

 its base ; upper median nervule convexly rounded at base and emitted from end of cell ; second from 

 a little before end of cell, lower at about one-third before end of cell; cell short and broad; sub- 

 niL'dtau nervure somewhat bent inwardly near base, and then outwardly along its apical half. Posterior 

 wings elongately and irregularly subovate ; costal margin obliquely convex, outer margin prominently and 

 angularly i>roduced at upper median nervule, from whence to anal angle the margin is more or less 

 concavely sinuate. Costal nervure short, extending to about half the length of costal margin; first 

 subcostal nervule emitted at about one-fourth before end of cell, second from end of cell ; upper median 

 nervule short and oblique, lower more than twice the length of upper and bent inwardly ; upper median 

 nervule from end of cell, second emitted at about half the distance from first as from third; sub median 

 nervure moderately bent outwardly ; internal nervure bent inwardly. Body moderately robust, pronotum 

 pilose; antennse short, with a gradually formed but distinct apical club; palpi short, compressed, broad, 

 and clothed with long adpressed hairs, apical joint minute. 



This genxis is of small extent, and may be taken as an Eastern representative of the genus 

 Gonepteryx* Dercas is found in Continental India, the Indo-Malayan region, and in China, 

 One species inhabits the Malay Peninsula* 



1. Dercas gobrias. {Tab. XXVI., fig. 18 $ .) 



fiuufptertjx Gohrias, Hcwitson, Trans. Ent. Soc. ser. 8, vol. it. p, 246, u. 6, t. 10 r f, 1 (1864) ; ButL Proc. Zool. 



Soc. 18G5, p. 432, t. 26, f. L 

 Bhotlocera Gohias, Voll. Mon. Pier, p. 63, □. 1 (1805), 



Dercm Gobrias, Wall. Trans. Ent. Soc. ser. 3, vol. iv. p. 398, u, 1 (18G7) j Draco, Proc. Zool. Soc. 1873, p,S56. 



Mule. Wings above bright sulphureous, the costal margin— especially near base— more or less 

 infnscated, the apex broadly dark chocolate-brown, — this patch is inwardly sinuate to discoidal nervule, 

 and then concavely narrowed outwardly; outer margin narrowly dark chocolate- brown, all the brown 

 markings narrowly inwardly margined with ochraceouB ; an ochraceous disco- cellular streak at end of cell, 

 and an oblique narrow ochraceous discal fascia. Posterior wings with the outer margin narrowly 

 chocolate-brown, the fringe reddish ochraceous. Wings beneath as above, but anterior wings with the 

 costal margin — especially near base — reddish ochraceous, followed by two small costal spots of the same 

 colour, the apical patch and outer margin paler than above, and the first with an oblique violaceous spot, 

 the disco- cellular spot and the discal fascia darker than above; posterior wings with some reddish 

 ochraceous markings at base, and with an oblique, narrow, discal, ochraceous fascia. Pronotum dark 

 greyish ; eyes castaneous; abdomen sulphureous; body beneath, with legs, concolorous with wings. 



Exp. wings, S t 65 to 08 millim. 



IIab.— Malay Peninsula ; Province Wellesley (coll. Disk) ; Perak (Kunst. — Calc. Mus.). — Sumatra 

 (Ilewits,). — Java (coll. Diet.). —Borneo (coll. G-odm, & Salv.). 



