COLUBRINE GROUP. 



203 



in front, we select the tesselated snake (T. tesselatus) and the nearly allied viperine 

 snake (T. viperinus), both of which are found in Europe, the former being a more 

 southerly type than the latter, and extending eastwards into South- Western and 

 Central Asia. The tesselated snake, which never grows quite so large as the 

 common ringed species, is olive or olive-grey above, and may be either uniformly 

 coloured, or marked with dark spots, usually arranged quincuncially, on the back. 

 The nape of the neck is ornamented with a dark chevron ; the upper labial shields 

 are yellowish, with dark lines of division between them ; and the under-parts are 

 either yellow or red mottled and marbled with black, or almost wholly black. 

 The viperine snake is rather smaller, having the upper surface grey, brown, or 

 reddish, with a zigzag black band down the back, and a row of yellow-centred 



/\ 



KEEL-TAILED SNAKE (J nat. size). 



black spots down each side. There is a more or less distinctly marked oblique 

 dark band on each side of the top of the head, and another on the nape of the neck ; 

 while the labials and under-parts are coloured like those of the tesselated snake. 

 The general habits of both these species are very similar to those of the ringed 

 snake ; but in spring they are more generally found concealed in pairs beneath 

 stones, and only take to the water in the summer. As other well-known North 

 American representatives of the genus, we may refer to the garter-snake (T. 

 ordinatus) and moccasin-snake (T. fasciatus) ; the former belonging to the first, 

 and the latter to the second section. As an example of the third section, in which 

 the last two or third upper teeth are suddenly enlarged, the Indian long-banded 

 snake may be mentioned. 



Oblique-Eyed Among the genera belonging to this section the only other that 



Snake. our space admits of even mentioning is the one containing the 



