278 Journal of the F.M.S. Museums. [Vol.X, 



The amount of black blotching upon the upper parts 

 of the frog is variable, and may be so extensive as almost to 

 obscure the green. Some specimens have the throat and 

 under surfaces of the thighs heavily marked with black also. 



The male has vocal vescicles fairly well marked 

 externally, the skin on either side of the jaw being thinned 

 and thrown into longitudinal folds. 



Rhacophorus leucomystax (Gravenh.). 



F.M.P., p. 248. 



Three examples from Kuala Tahan and many from 

 Eraser's Hill. In some of these the tibio-tarsal articula- 

 tion reaches the tip of the snout, in others well beyoncj. 

 The hind leg of this common tree-frog varies greatly 

 in length, and in the large series in my possession from 

 Siam and Indo-China, the tibio-tarsal articulation reaches 

 beyond the snout in more than half of them. Philippine 

 examples evidently do the same (cf. Taylor, Philippine 

 Amphibia, 1920, p. 289). 



Rhacophorus bimaculatus Bouleng. 



F.M.P., p. 250. 



13 exs. Bukit Fraser. 



This tree-frog is very closely allied to R. reinwardti 

 Boie, and I doubt if it should really be considered specifi- 

 cally distinct. I have compared the above examples, 

 and 24 more from Khao Luang in the Nakon Sritamarat 

 Hills, Peninsular Siam (unfortunately, only one more than 

 half grown) with 4 specimens of typical reinwardti from 

 Java. None of the differences claimed by Boulenger for 

 them will stand. 



The vomerine teeth may be in slightly oblique series 

 or perfectly straight. The cutaneous folds above the vent 

 along the sides of the arms and legs may be slightly or 

 strongly developed. No black spots are present on the 

 membrane between the fingers and toes of the Siamese 

 examples, but are present in half the series from the 

 Malay Peninsula. 



The character in which the two forms however do 

 consistently differ is in the size of the discs of, and extent 

 of the web between, the fingers and toes. In reinwardti 

 the finger discs are always larger than the tympanum and 

 the membrane is fuller, usually extending to the disc of 

 the third finger. In bimaculatus the discs are not larger, 

 and often smaller, than the tympanum, and the web never 

 reaches the disc of the third finger. 



In addition the membrane of both fingers and toes 

 in reinwardti are wider, allowing a more complete 

 separation of the digits. Thus when the fingers of this 

 frog are fully extended, the first and fourth form a straight 



