SERPENTS. SXAKE. 



SERPENTS. 



These animals are distinguished from the other amphi- 

 bia, by their want of feet ; their motions being made by 

 means of their scales and general writhings. The pois on- 

 ous serpents may be distinguished by the structure of their 

 teeth. The poisonous fangs, or teeth, are mostly larger 

 than the others, and of a tubular construction ; they are so 

 situated, that the animal can raise or lower them at its 

 pleasure. The fangs are always placed near the edge, at 

 the. front of the upper jaw, and have communication with a 

 peculiar reservoir which contains the poisonous fluid. 

 They in general lie with their points bent inwards, but 

 are quite erect when the animal is provoked. It may be 

 considered as a rule, that the poisonous serpents have 

 only two rows of proper teeth in the upper jaw, while the 

 other species have four. Most of the poisonous species 

 have heads covered with small scales ; and their scales in 

 general have a raised ridge passing through their centre. 

 All serpents cast their skins at certain periods ; in tempe- 

 rate climates annually ; oftener, perhaps in the warmer 

 regions. In temperate and cold climates they conceal 

 themselves under ground, to pass the winter in a state of 

 greater or less torpidity. Some serpents are viviparous, 

 especially the poisonous species : but by far the greater 

 number are oviparous, and deposit their eggs in a kind of 

 chain, in some warm and close place, where they are 

 hatched. 



THE SNAKE. 



This is the largest of British serpents, sometimes ex- 

 ceeding four feet in length. The neck is slender; the 

 body swells in the middle ; the back and sides are covered 

 with small scales; and the belly with oblong, narrow, 

 transverse plates. The colour of the back and sides is 

 dusky brown ; along the middle of the back run two rows 

 of small black spots, reaching from head to tail ; and from 

 them proceed numerous lines of spots, crossing the sides. 

 The plates on the belly are dusky ; those on the sides are 

 of a bluish-white colour. On each side of the neck is a 



