REPTILIA— AMPHISB-ENA. 709 



pointing forward ; these horns have nothing analogous in their structure to 

 the horns of quadrupeds, and are by no means to be considered in the light 

 of either offensive or defensive weapons ; they are moveable, and about one 

 sixth of an inch long. 



The head of the cerastes is flattened ; the muzzle thick and short ; the eye 

 yellowish green. The hind part of the head is narrower than the part ni 

 the body to Avhich it is attached. The scales of the head are of the same 

 size with those on the back, or only a little less ; and all the scales are oval 



with a longitudinal ridge. The general color of the back is yellowish, with 

 irregular spots of different degrees of darkness, in form of transverse bands. 

 The under surface of the body is brighter. The cerastes inhabits the' great- 

 est part of the eastern continent, especially the desert sandy part of it. It 

 abounds in the three Arabias, and in Africa. In Egypt, it appears to be par- 

 tially domesticated, as it will enter the houses when the family are at table, 

 pick up the scattered crumbs, and retire without doing injury to any one. 



This animal can endure hunger and thirst much longer than most serpents ; 

 some naturalists assert that it can exist five years without nourishment. 



THE AMPHISB^NA.i 



This genus grows usually to the length of one or two feet, of which the 

 tail never exceeds an inch, or an inch and a quarter. It is from the extremi- 

 ties of its body being of an equal thickness its being supposed to crawl in 

 both directions, that it derives its name. The eyes are exceedingly small, 

 and covered in such a manner by a membrane, as to be hardly perceptible : 

 from which circumstance it has been called the blind serpent. The top of 

 the head is covered by six large scales, in three rows of two each ; and the 

 body is*entirely covered with smooth scales of an almost square form, arrang- 

 ed in regular transverse rings. It has a hard skin of an earthy color. 



' The genus AmphkhcBna has the body surrounded with circular rows of quadrangular 

 scales; a row of pores before the anus; teeth not numerous, conical in the jaws only; ovi- 

 parous. 



60 



