■0 JOURNAL, NATVBAL HIST. SOCIETY OF SIAM. Vol.. I. 



at the base of the tail and another at the end, has been figured hy 

 Guiither (Kept. Brit. Ind., pi. XX. fig. A). The other, with 19 

 rows of scales and without the spots on the tail has been described and 

 figured by Jan as S. quculrilineatus. Unfortunateh^, the latter name 

 is a strict synon^'m of S. taeniaius, Giinther's original description 

 (P. Z. S. 1861, p. 189 ) having been drawn up from a single specimen 

 of the same form ; so that 1 am compelled to propose a new name, 

 var. MouJioti, for the snake figured in the Reptiles of British India. 

 I should have regarded these two forms as species, as Dr. Malcolm 

 Smith, who has examined many specimens, finds them always quite 

 distinct from each other, but for the fact that a specimen from Laos in 

 the British Museum combines the number of scales of S. taeniaius 

 with the coloration of S. MouJioti. Dr, Malcolm Smith further points 

 out a difference in the colour of the tongue, which is entirely reddish 

 in the former, and black at the base and at the tips in the latter. 



[I have now examined altogether some 40 specimens of these 

 two forms from various parts of the country, and the fact that I had 

 so far always found them distinct from each other, led me to think 

 that they should be ranked as species. Both are eqnall}' common in 

 Bangkok, but the form with 19 rows of scales is rare outside. The 

 following are the various points of difference, drawn up from notes of 

 m}' own specimens. 



S taeniatus. 

 (Drawn up from 15 specimens.) 



19 rows of scales. 

 Tungue red. 



Posterior head-mark arrow 



shaped. 

 No tail-bars or collar. 



Suhocular rarely preseiit. 

 Ventrals 155— 1G7. 

 Temporals 2 + 2, rarely 1 + 2. 



S. MouhofA. 

 (Drawn up from 25 specimens.) 



17 rows of scales. 



Tongue black at the base and 



tips. 

 Post erior head-mark heart 



shnped. 

 1 or 2 tail-bars and a more or 



less comjilete collar, (Any or 



all occasional]}^ absent). 

 Subocular generally present. 

 Ventrals 144-163. 

 Temporals 1 + 2, rarely 2 + 2. 



I should be grateful to any member of the Society who will 

 forward me furthi^r s] ecimeus for examination. A description of tlie^ 

 two forms will be found in the article on the Snakes of Bangkok, in 

 this number.— M. S.] 



