1895.] L. de Niceville & Dr. L. Martin — Butterflies of Stimatr a. 495 



It is treated by Tinmen as a purely African butterfly. The original 

 figure does not at all agree with the original figure of T. drona, Hors- 

 field = T. libythea, Fabricius, as it has no black border to the hindwing 

 on the upperside. Watson in Journ. Bomb. Nat. Hist. Soc, vol. viii, 

 p. 515 (1894) says that T. drona as identified in the British Museum has 

 the "marginal band of hindwing evenly narrow throughout." This is 

 incorrect, as a glance at the original figure will show, at the costa it is 

 broad, fining away to nothing at the anal angle. Butler states in 

 Ann. and Mag. of Nat. Hist., fifth series, vol. xvii, p. 221 (1886) that 

 the unique specimen described by Horsfield is a female. I doubt 

 this, I should say it was a male, as it is clear yellow on the upperside; 

 were it a female it would have a heavy sprinkling throughout of black 

 dots. It therefore agrees in this character with T. libythea, which is 

 defined by Watson as having the " marginal band of hindwing broad 

 at apex and narrow at anal angle." Butler in Cat. Fab. Lep. B. M., 

 p. 227, says that T. libythea is " an unspotted variety of Horsfield's 

 T. drona." From a careful examination of my series of Terias of this 

 group, it appears to me that T. libythea (following the identification 

 of this species in the British Museum) is the dry-season form, with 

 T. rubella, Wallace, as a synonym, and T. drona the wet-season form, 

 with T. senna, Felder, as a synonym, of one and the same species. 

 The wet-season form ( T. drona) alone occurs in Sumatra. In Sumatra 

 it is found only on the Central Plateau of Tobah and Karo, and even 

 there is not very numerous and occurs only at certain times. Though 

 the collectors were instructed always to catch this species when they 

 could, they only brought in specimens in December and January, when 

 it appears to be common, and in May and July, when it appears to be 

 rare, and not a single one in any other month, so the species in 

 Sumatra would appear to be double-brooded. 



539. Terias tilaha, Horsfield. 



Hagen. Sumatran specimens have a reniform mark at the end, 

 and a W-shaped mark ab the middle of the diseoidal cell of the forewing 

 on the underside. The female is paler on both surfaces than the male, 

 of a lighter more gamboge-yellow colour, with the marginal band on 

 the upperside of the hindwing twice as broad, narrow at the apex, very 

 broad at the anal angle, and extending on to the disc on either side of 

 the submedian nervure. It is the rarest Terias of our area, found 

 throughout the year on the outer mountains and also in the plains, as 

 several specimens have been obtained at Selesseh, though Dr. Hagen 

 says that it is not found below an elevation of 500 feet. In 1887 Dr. 

 Martin took a specimen at the Terdjoen Estate very near the sea. It 



