CLAWS 77 



others, such as the frilled lizard, like the mammalian 

 raccoon, are flat-footed when going slowly and toe- 

 walkers when in a hurry. 



The number of joints in the toes of lizards is 

 especially interesting in that they have the same 

 order in number that occurs in the birds. The bird, 

 however, lacks the fifth toe. The first toe has two 

 joints ; the second toe, three joints ; the third toe, 

 four joints ; the fourth toe, five joints ; and the fifth 

 toe the same as the third, four joints. But in some 

 old paddle-limbed kinds of reptiles there were a great 

 many joints in the digits, as there are in the paddles 

 of the fringe-finned and other fishes now. 



Besides the serpents, many lizards are limbless, as 

 are the Arnphlshcena (no English name), and the so- 

 called slow worms {Anguis) of the Old World, the 

 glass-snake or joint-snake (Fig. 39) (which is a lizard 

 — Ophimju'us) of America, and many others found 

 in the famihes of skinks, greaved lizards, and other 

 groups. In some of these the rear pair of limbs 

 only may remain, and in others the fore pair only are 

 present. 



It is well known that most serpents are limbless; 

 but the family of crushing or constricting snakes 

 {Boidm), boas, pythons, and anacondas, and many of 

 their near-by kin, show rudiments or stumps of limbs 

 at the rear end of the body. In some other families 

 near to these, the stumps do not show, yet the little 

 bones to which the hind legs are usually attached — 

 the so-called pelvic girdle — are found beneath the 

 skin. But no vestige of a fore limb, or of the 



