SOME UNDESCRIBED RHOPALOCERA FROM SIAM. 183 



B. M. Type No. Rh. 129, d, Me Song forest, Prae, N. Siam, 

 17. 4. 1916. 



Another specimen was obtained in the same locality on the 

 following day, whilst a third is in the British Museum from Tilin 

 Yaw, Upper Burma, 17. 4. 90, collected by Watson. 



This species has points of resemblance to both A. uranus 

 Butler, and A. ubouldus Cramer. From the former it can at once be 

 separated by its very broad dark margins and the darker tone of its 

 underside, although it agrees very closely with it in underside, 

 markings. From the latter it can as easily be distinguished, apart 

 from the colouration of the upperside and the more rounded shape of 

 its wings, by the absence of any trace of the basal streak on the 

 underside of the forewing. It is also slightly larger than normal 

 examples of the other two species mentioned. 



AltHOPALIN^E. 



17. Arhopala dispar, sp. nov. 

 (Plate VI, fig. 8.) 



6 . Upperside, both wings. — Bright lilacine blue. Forewing. — 

 A darker transverse mark at end of cell, the central area of wing paler, 

 almost white in parts. Hindwing. — Costal area dark brown, marginal 

 areas shaded with brown, tails dark brown, abdominal areas white. 



Underside, both wings. — Ground-colour dark shiny brown 

 with a faint dull purplish tinge. Forewing. — Areas la, 16 and 2 

 almost pure white; the three cell spots, costal spot and anterior 

 part of transverse band all large and very dark brown, ringed or 

 bordered with white ; remaining spots also large but paler ; the spots 

 of transverse band oblong, the uppermost one reaching the costal spot 

 (above cell-end), the next three in a regular row, very close to the 

 third (distal) cell-spot, the two below, in areas 3 and 2, moved inwards 

 so that the upper one touches the third cell-spot and also its extension 

 in area 3; a large spot fills the base of area 2, and a very large irreg- 

 ular spot in area 16 extends from base to well beyond origin of vein 

 2 ; there is a shadowy submarginal series of spots slightly darker 

 than the ground-colour and relieved with grey either side. Hindwing. 

 — The costal basal spot, the basal row of four spots, of which the 



VOL. IV, NO. 3, 1921. 



