268 



VERTEBRATE ANIMALS. 



the poison-faug. The head is broad, somewhat triangular in shape, broadest 

 in its middle, and showing a very distinct line of demarcation between the head 

 and neck. The head, also, is usually covered with small scales (fig. 193, C), 

 and rarely exhibits large plates or "scnta." The Crotalids have a deep pit 

 between the eye and the nostril, by which they are distinguished from the true 

 Vipers, and from which they have acquired the common name of " Pit- vipers." 

 (2.) The Ebipina are poisonous Snakes, in which the poison-fang.s are per- 

 manently fixed and erect, and have smaller solid teeth behind them. The head 

 (fig. 193, A) is shield-shaped, and not much wider than the body, its upper 

 surface being covered with large shields or scuta. This group comprises some 

 of the most deadly of all the Serpents, one of the best known being the Hooded 

 Snake or Cobra di Capdlo {Naja triimdians), which is commonly found in 



Fig. 19.3. — Ophidia. A, Head of an Elapine Snake (Bungar^is fasciatils), viewed from 

 above. B, Iltad of a Colubrine Snake (Tropidonotus natrix). C, Head of a Viperine 

 Snake (Dahoia Ku^sellii). (A and C are after Sir Joseplt Fayrer; B is after Bell.) 



Hindostan, and is the snake usually carried about by the. Indian snake- 

 charmers. It varies from two to six feet in length, and the neck can be 

 extensively dilated, covering the head like a hood. A nearly allied species is 

 the jVflyVx haje (tig. IS9) of Egypt. The genus Bnngarus, including the deadly 

 " Kerait " {B. crnleus) of India, is nearly allied to Kixja, but the neck is not 

 dilatable. America has representatives of this family in the beautifully marked 

 Coral-snakes and Harlefpiin-snakes (Elaps) ; and they abound in the Australian 

 region, a well ];nown type being the Death-adder {Acanihophis). 



(3.) The Jli/ih-iiphiihi comprise aquatic Ophidians which have the tail ver- 

 tically cominessed and broadened out. They are found principally in the 

 Indian and Chinese seas, often frequenting the mouths of rivers, though some- 

 times ranging far from land. They are extremely poisonous, and swim with 

 great ease and rapidity. 



