LIZARDS. 



433 



The snake-like body is unprotected by scales except in the region of the head and 

 throat, and the skin is divided by closely arranged, transverse constrictions, and by 

 more shallow longitudinal furrows into oblong divisions, which give the animals, often 

 assisted by their peculiar color, a mosaic-like appearance. The pectoral girdle is very 

 rudimentary, except in a single genus, and the sternum is never present. The pelvic 

 arch is represented by rudiments, though it never bears appendages. The bones of 

 the skull are firmly articulated together, and the. rami of the lower jaw are united in 

 front by an unelastic symphysis. The eyes are small and, like the ears, covered by 

 the integument. The teeth may be either placed along the ridge of the jawbone, 

 acrodont, or along the inside, plurodont. 



The genus Amphisbcena has the teeth plurodont ; two large nasal shields, behind 

 which are two pairs of frontals ; the head flat with a rounded snout ; and in front of 

 the vent a transverse row of so-called pre-anal pores. The generic name has been 

 given because of a popular notion that the animal, which can progress in either way, 

 is provided with a head at each end, the short rounded tail resembling the head in 

 general outline. The sooty Amphisbsena, A. fuliginosa, is the most common species, 



kUCNSUlA^NNs 



Fig. 249. — Amphisbcena alba. 



and is found throughout the warmer portions of South America, where it hides in the 

 ground, through which, like the earthworm, it tunnels its way in search of larvae. The 

 young of ants form the chief element of its diet. 



JRhineura floridana is an allied form. This animal, the only native member of 

 the family, has been many times captured in Florida, where, from its habit of leaving 

 its subterranean home and coming to the surface after thunder showers, it has received 

 the name of ' thunder-worm.' It is of a dirty white color, on the upper surface of the 

 head becoming yellowish. 



Also of subterranean habits, though differing from the other members of the 

 family in having a pair of small limbs terminated by five toes, is Chirotes, a genus 

 inhabiting Mexico and Lower California. The head is no larger than the rest of the 

 the body, the teeth are conical and slightly recurved, and the tongue, like that of the 

 woodpecker, is tipped with horn. On the abdomen is a row of pores resembling those 

 of Amphisbcena. 



We now come to an Old World family, the Laceetid^, which is represented by 

 several genera. 



J'seudopus is found in Europe and southern Asia. It has the body long and snake- 

 voL. ni. — 28 



