608 OPHIDIA CHAP. 



T. natrix, the common Grass-Snake, has a divided, or double, 

 anal shield. The strongly keeled scales of the body form nineteen 

 rows. There are normally seven upper labials, the third and 

 fourth of which border the eye. The usual colour of the Grass- 

 Snake is olive-grey or brown above, with black spots and narrow 

 cross-bands. The labials are white or yellowish, with black 

 sutures. The belly is checkered black and white, more or less 

 suffused with grey. There are several colour-varieties. The 

 typical or northern form has a white, yellow, or orange collar, 

 bordered behind by a black collar; the pale collar is sometimes 

 faint or absent. The second variety, rather common in Spain 

 and Portugal, although not the only form in the Peninsula, has 

 no collar whatever, and these specimens are sometimes almost 

 uniformly grey -green above. The third variety, common in 

 South -Eastern Europe and in Asia Minor, has a well-marked 

 collar and a yellowish streak along each side of the back. But 

 there are also almost black specimens. 



The usual length of an adult female Grass-Snake is about 

 3 feet, but very exceptional cases of more than 6 feet are on 

 record ; the males are smaller and more slenderly built. The 

 range extends over the whole of Middle Europe, Algeria, West 

 and Central Asia. It does not, however, occur in Ireland or 

 Scotland. Its northern limit is the southern part of Sweden. 



The Grass -Snake prefers moist, grassy localities, with the 

 neighbourhood of water, chiefly on account of the food, which 

 consists entirely of fishes and Amphibia, notably of frogs ; 

 tree-frogs are preferred to anything else ; toads are occasionally 

 eaten, but mice are never taken. 



The Grass -Snake can climb trees or rather shrubs and is 

 an accomplished swimmer, often spending much of its time in 

 water for fishing purposes. The fish is caught by the belly and 

 then generally swallowed on land. The Grass-Snakes appear 

 in the spring and disappear in the autumn to hibernate in the 

 ground. They pair, in England, in the month of May or June, 

 usually on warm and sunny mornings. The eggs are laid from 

 July to the end of August, mostly in rich vegetable soil, in 

 heaps of weeds or in manure-heaps. Young snakes lay fewer 

 eggs than old specimens, which sometimes produce more than 

 three dozen at a time. The eggs are soft, whitish yellow, about 

 one inch long, and soon stick together, so that the whole clump 



