156 LIZARDS. 



together with eggs. The female lays from fifty to sixty hard-shelled eggs about 

 the size of those of a pigeon, generally placed in the hillocks of white ants. 



The dracsena (Draccena gwianensis), of the Guianas and Amazonia, is a 

 somewhat smaller lizard, distinguished by its compressed and doubly-keeled tail, 

 the intermixture of keeled tubercles among the scales of the back, and the 

 extremely broad crowns of the cheek-teeth. 



Our second figured representative of the family is the Surinam 

 The Ameivas. . . 



ameiva (Ameiva swrinamenaw), belonging to a genus or nearly 



twenty species distributed over Central and South America, where they take the 

 place occupied by the true lizards in the Old World. They are distinguished by 

 their round, keelless tails, the presence of less than twenty rows of large smooth 

 scales on the under surface of the body, and the compressed two- or three-cusped 

 cheek-teeth. The tongue can be withdrawn into a sheath. The figured species, 

 which is found over South America as far as Nicaragua, attains a length of from 

 15 to 20 inches, and is very variable in coloration. The young are olive-brown, 

 with darker markings or white dots, and a black, white-edged band running along 

 the side of the body and extending on to the tail ; these bands generally disappear- 

 ing with age, although sometimes retained in the females. In the adult the upper 

 surface is usually greenish, with some black and a few white spots ; while the 

 under-parts are greenish white, spotted with black on the sides. Ameivas are 

 generally found in dry districts more especially near the coasts, and in their 

 general habits are not very different from the teju, usually living in holes, among 

 old wood, or the herbage of gardens. 



THE AMPHISB^ENAS. 

 Family AMPHISB^NID^K 



Among the most remarkable of all lizards are those whose typical repre- 

 sentatives have the power of moving equally well either backwards or forwards, 

 from whence they derive the name by which the group is now commonly 

 designated. Very nearly related to the preceding family, through those members 

 of the latter with aborted limbs, the amphisbsenas are distinguished by the simple 

 and degraded characters of the skull, in which all the arches have been lost, 

 and the two premaxillary bones are fused into one. All are adapted to a purely 

 subterranean existence, and have long, worm-like bodies, devoid, except in one 

 species, of any external trace of limbs ; while even the bones of the shoulder and 

 pelvis are more or less rudimental. The eyes are concealed beneath the skin ; the 

 mouth is small, and frequently inferior in position; and the ear is completely 

 wanting. Although the head is covered with large symmetrical shields, the skin 

 of the body is divided into squared segments forming regular rings, like those of 

 worms; from which character the group is sometimes spoken of as the ringed 

 lizards. In all the tail is short. The large teeth are few in number, and fixed 

 either to the inner or upper edges of the jaws. 



The amphisbsenas, which are arranged in eleven genera, including between 

 sixty and seventy species, are most numerously represented in America south of 



