SERPENTS. 



387 



commences with the head, which by main force it thrusts into its 

 mouth, the jaws becoming widely separated, so that the throat is 

 stretched enormously as the food is forced into it. Deglutition is 

 here a very lengthy and laborious process, and was there not some 

 special contrivance to guard against such an accident, no sooner 

 were the efforts of the snake relaxed in the slightest degree, than 

 the muscles of the throat and jaws being in an extreme state of 

 tension, would force out of the mouth what had already been 

 partially swallowed. To provide against this, the teeth are by 



FlG. 319. SKULL OF PYTHON. 



their position converted into a sort of valve. Pointing backwards 

 as they do, they permit the bulky food to pass down towards the 

 throat, but at the same time their sharp points efficiently prevent it 

 from being pushed back again in the opposite direction. 



" facilis descensus Averni 



" Sed revocare gradum, superas que evadere ad auras 

 *' Hoc opus hie labor est." 



The largest of all the Boa family, and perhaps the largest of the 

 Serpent race, is 



The Anaconda (Eunectes murinus), found only on the American 

 continent. It is to this species that we must refer the greater 

 number of the highly-exaggerated tales of travellers relative to the 

 enormous size, ferocious habits, and extraordinary voracity of the 

 monstrous serpents of the new world. Still it is quite formidable 

 enough ; one of its provincial names, El Traga Venado, or the Deer- 

 swal lower, sufficiently indicates the idea entertained by the Indians 

 relative to the nature of its food. 



The Harmless Snakes (Colubridse) form a very ex- 



FlG. 320. HKAD OF RINGED SNAKE. 



FlG. 321. BELLY AND TAIL-SHIELDS. 



s 2 



