TADPOLES FROM SIAM. 263 



rather low, upper a little deeper than lower, not extending on to the 

 back. 



Moiiili. Small, on the ventral surface: shortish papillae at the 

 sides and below. Beak broadly edged with black. Tapper lip with a 

 loaj,', continuous row of teeth, followed by a second, broadly interrupted. 

 Lower lip with three continuous rows, or the upper one narrow)}' in- 

 terrujited ; the lowest row about half the length of the first or second, 

 which are subequal. 



Dimensions:. Total length, io ; head and liady, 16 ; depth of 

 tail, 7 mm. 



Coluur (in life). Olive above speckled with blackish, below 

 nearl}- colourless (Iti spirit, whitish). 



Nunibprs of these tadpoles in all stages of development, and 

 young ones which had left the water, were obtained upon Dji Nga Ciiang 

 early in Marcli, at between 700 and 1,000 metres elevation. In company 

 with them were the larvae of yfpqahiplii'ijs montina and .1/. pelodi/tuides. 



Raua rugulosa Wiegin. 



Jf'ina t/</nna, Flower, V Z.S.. ISOO, p. 892, pi. LIX. 

 Rnna riiipilii^n, Aiinaiiilale, -Mem. Asiat. Soe. Bengal, VI, p. 12G, fig. 

 •2 and" pi. VI (1917). 



I have obtained two distinct forms of this tadpole in Bangkok, 

 one wilh a long snout and elongated body, the other with a shorter 

 snout and more rounded body. This variafion is quite independent of 

 age, and the figures given, showing the difference, have been drawn 

 from fully grown examples. Flower's illustration is evidentlj- from 

 the shorter form, where the length of the boly is about H times its 

 width. Ill the longer form it may be nearly twice its width. A some- 

 what similar differenca in form has been figured b}' Annandale for the 

 tadpole of the closely allied R. tiijrina, showing the variation in the 

 position of the nostril. It will be observed that the position of the 

 nostril wilh regard to the e3'e does not alter, the variation being in the 

 length of the snout beyond, the greater portion of which, being absorb- 

 ed in the completion of development, has no anatomical value in after 

 life. 



Concerning the aruiature of the mouth Flower remarks (p. 893), 

 " inside the uiipei' lip are five s^-ies of line, black teeth: the first 



VOL. n, DEC. iiiir. 



