BATRA.CHIANS FROM SOUTHERN ANNAM. 427 



Olive-brown above, uniform (no longitudinal lines or collar), 

 below yellowish-white, with a median line along the tail and 

 usually another down the belly. Labials yellow. 



10 examples examined. Variation: r? . Y. 143-149 ; C. 30-34. 

 9. Y. 166, 167; 0. 18, 19. 



Type locality, Langbian peaks at 2000 meti-es. 



Type series, AuthoVs Nos. 2135, 2136, 2137, and 2139. 



Trimeresurus monticola Giinther. 



Lachesis monticola, Cat. Sn. B. M. iii. p. 548 (1896). 



1 ex. The specimen differs from the recognized description in 

 having all the subcaudal shields single, and in having only two 

 rows of scales between the eye and the labials. Wall, however, 

 records one from the Chin Hills (Journ. Bombay N. H. S. xx. 

 p. 775), in which the subcaudals are irregularly single and paired, 

 and I find in the British Museum an example in which there are 

 only two rows of suboculars. For the present, therefore, I regard 

 my specimen as T. monticola. Scales 21, 15. Anal 1. Y. 132. 

 C. 38. Six scales between the supraoculars. 



Gymnouactylus peguensis and subsp. 



G. peguensis, Bouleng. Rept. Malay Pen. p. 36 (1912). 



Two specimens of a G i/ninodactylus obtained at Camly agree 

 well in characters with the typical form of G. peguensis, but 

 differ distinctly in colouration. Both are males, and in both tlie 

 tails are missing, and it is possible, with more complete material 

 for examination, that the present diagnosis will be found in- 

 correct. I refer them here to G. peguensis, and at the same 

 time take the opportunity to describe another colour race which 

 I have obtained in Eastern Siam. 



The three forms may be described as follows : — 



Gymnodactylus peguensis, forma typica. (Text-fig. 1, A.) 



7-8 prfeanal pores ; 9-1 1 upper and 7-9 lower labials ; two 

 series of (6-8) lai-ge round spots on the back, or with the spots 

 confluent transverse]}^ Head in the adult with lai-ge rounded 

 spots. 



Type locality, Palon, Pegu. Has been found also in other 

 parts of Pegu and in Peninsular Siam as far nortli as Nakon 

 Sri Tamarat. 



Yar. ANG'ULARis, nov. (Text-fig. 1, C.) 



10-11 upper and 9-10 lower labials; two series of (4) lai^ge 

 angular spots connected mesially. Head in the adult witti 

 indistinct angular spots. 



Habitat. Dong Rek Mts., Eastern Siam. 

 Proc. Zool. Soc— 1921, No, XXIX. 29 



