190 THE LIVING ANIMALS OF THE WORLD 



Snakes, like lizards, are most abundant in tropical countries, the Indian and Malay regions 

 in particular being richest in numbers and varieties. The British Islands support but three 

 representatives of the class — the Adder, the Common Ringed and the Smooth Snakes — this 

 number, by a coincidence, being identical with that of the Lizard Tribe indigenous to the 

 same islands. Many of the smaller species are little over i foot long, while the huge Pythons 

 and the Anaconda may attain to or exceed 30 feet. Regarding their habits, some are purely 

 terrestrial, frequenting the rocks or sandy deserts, or even burrowing beneath the earth's 

 surface. Others are essentially arboreal, many amphibious, and some, like the Turtles among 

 the Chelonians, entirely marine. As with the Lizards, the majority of snakes lay eggs enclosed 

 within a white leathery shell, while with a considerable number the young are brought forth 

 alive. The eggs, deposited in the earth, sand, or among vegetable debris, are usually left to 

 be hatched by the heat of the sun. In the case of the P_\'thons, however, they are incubated 

 by the parent. 



A small group of snakes which is usuall)- placed at the head of the series in systematic 



classifications share the sub- 

 terranean habits of the 

 Amphisbffinas among the 

 Lizards ; and the eyes being 

 rudimentary and functionless, 

 they are commonh- known as 

 Bl.lND-SN.VKES. A structural 

 peculiarity which separates 

 these singular reptiles from 

 all other members of the 

 Snake Tribe is the entire 

 absence of teeth from either 

 the upper or lower jaw. The 

 food of the blind-snakes 

 consists largely of ants and 

 the larvae of beetles and 

 other insects which lead a 

 subterranean life. Although 

 spending the greater portion 

 of their existence under- 

 ground, they occasionally 

 come out upon the surface, 

 such migrations more gener- 

 ally taking place during 

 showery weather. About 100 species of blind-snakes are known, and are mostl}^ confined to 

 tropical countries. One small worm-like form occurs in Greece and the adjacent islands, its 

 range extending through a considerable area of South-western Asia. 



The steps from the small worm-like Blind-snakes, with their functionless eyes and under- 

 ground habits, to the Boas and Pythons, the largest and most highly organised members of 

 the Serpent Tribe, would seem at first sight to be altogether unwarranted. In one essential 

 character, however, they agree very remarkably. In botli groups the bony skeleton exhibits 

 a far more generalised structural plan than in any of the succeeding ones, so that they may be 

 regarded as more nearly resembling the primitix'C stock from which the other more specialised 

 kinds — such as the Vipers, with their death-dealing poison-fangs — have been evolved. 



The Pythons and Boas, or Boa-CON.strictors, as they are popularly known, belong entirely 

 to the non-venomous section of the Snake series. The teeth, forming two rows in the upper 

 jaws, gradually decrease in size from before backwards, and none of them are grooved or 

 modified in the form of poison-fangs. The body is usually more or less compressed, and the 



US' 



Phili tf IV. P. Dondc, F.Z.S.] [Rtgrr:!'! Park 



BOA-CONSTRICTOR READY TO STRIKE 



The neck^ throivn hack in 01c or more laops^ can be pro]ected^ luith immcvse Jorce and lightning- 

 like rapiJit\^ to strike or ief-L-e ari intended Tuam. 



