184 MESSRS. RILEY AND GODFREY ON 



third is oval and the fourth, and lowest, much the innermost, and 

 the median row of three larger spots, of which the lowest is very long 

 and lanceolate, are all very much darker brown than the ground- 

 colour and very clearly ringed with white. The broad irregular spot 

 at end of cell and the spots of the discal series are slightly paler. The 

 latter is interrupted at veins 6, 4 and 2, and has the spot in area lc 

 V-shaped, that in area 16 very long, lanceolate, nearly reaching 

 the lowest spot of the basal series. There is a darker rather 

 indefinite wavy grey-edged submarginal line and a marginal series 

 of very indefinite brown crescentic spots in areas 6 to 3, continued 

 by a similar but black spot in area 2, a large round black spot heavily 

 blue-scaled in area lc and a much smaller one only slightly bluish in 

 area 16. A conspicuous feature is the replacement of the ground- 

 colour in the whole of area 6 and in the adjacent distal parts of areas 

 5 and 7 by light greyish. 



Length of forewing. — 25 mm. 



B. M. Type No. Rh. 130, tf , Me Song forest, Prae, N. Siam, 

 April 1918. 



Similar to A. camdeo Moore, but smaller, and most readily 

 distinguished by the purplish-brown tint of the underside, the more 

 even colour of the darker markings, which are also in proportion 

 larger than in camdeo, the very different shape of the lowest spot of 

 the median series of the hindwing ( we use the terminology of 

 Bethune-Baker in his Revision of the Arhopalinae in the Trans. 

 Zool. Soc. London, 1903 ), and the whiteness of the inner-marginal 

 area of forewing and of area 6 of the hindwing. 



Another male, which we consider to be a form of this species, 

 was taken at the same time and place as the Type, but differs in 

 being of a rather brighter blue above and very much lighter and less 

 heavily marked below. The differences given above, however, serve 

 equally well to separate it" and the Type of dispar from A. camdeo 

 Moore, with the Type of which both specimens have been compared. 

 18. Arhopala opalina (Moore). 

 ( Plate VI, fig. 7. ) 



Nilasera op; din' i, Moore, Proc. Zool, Soc. London, 1883, p. 531, 



pi. 49. fig. 1. 



JOURN. NAT. HIST. SOC. SIAM. 



