206 DR MALCOLM SMITH ON 



Total length 450 mm ; tail 165. 



Black above with a dor so-lateral chain of yellow spots ; outer 

 two rows of scales with yellow centres; labials yellow with black 

 sutures, and a yellow streak from the angle of the mouth on to the 

 nape. Below yellowish, with a black spot at the outer edge of each 

 ventral and subcaudal shield. 



Variation. Four others (juveniles) taken in the same 

 locality show no variation from the type specimen, except in the 

 number of the ventral and caudal scutes, and in the colour of the 

 head, which is light brown above with yellow vermiculations. 



Natrix groundwateri is named after Mr. C. L. Ground- 

 water, to whom I have been indebted on many occasions for 

 illustrations which have appeared in this Journal. It is allied to 

 N. inas (Laidlaw) from the hills of Perak and Peninsular Siam. 



Measurements in mm. 



4437 230 85 151 ? 



Type presented to the British Museum. Paratypes in my 

 own collection. 



The illustration is twice the natural size. 



Natrix nigrocinctus (Blyth). 



Tropidonotus nigrocinctus, Blyth, Journ. Asiat. Soc. Bengal, 1856, 



xxiv., p. 717; Bouleng., Cat. Sn. B. M., 1893, i, p 255; 



Smith, Journ. Nat. Hist. Soc. Siam, 1915, i, p. 244; id., ibid., 



1916, ii. p. 159. 

 Tropidonotus eisenhoferi, Gyldenstolpe, Iv. Sv. Vet. Akad. Hand., 



1916, Band 55, No. 3. p. 11, text fig. 



A series of 19 examples of this snake from Siam shews it to 

 be a very variable species. The collection includes examples from 

 three well separated localities — from northern Siam nearest to the 

 type locality (Pegu), from Peninsular Siam and from S. E. Siam* 



JOURN. NAT. HIST. SOC. SIAM. 



