SAURIANS. 477 



(3) Geckotida, Geckos ; (4) Iguanida, Iguanas ; (5) Varanida, 

 Varans; (6) Teidce, Teguixins; (7) Lacertida, Lizards; (8) 

 Chalcida, Chalcides ; (9) Scincidce, Scinks. 



FIRST FAMILY. CROCODILES. 

 CrocodiHda, (Gr. xQoxodsdog, krokodeitos, a crocodile.) 



This family includes three genera, closely related to each 

 other, and agreeing in the general details of their structure. 

 They are the largest of the Lizards found in America. They 

 are called Alligators in the southern parts of the United States, 

 and Caimans in the Antilles and South America. In Africa and 

 Asia they are called Gavials. Those of America are distin 

 guished by a broad and rounded snout; those of Africa by an 

 elongated flat snout, and those of Asia by a pointed one like the 

 beak of a bird. They differ from other reptiles in the tongue, 

 which is thick, flat, and attached so much to the mouth that the 

 ancients believed this member was altogether wanting. &quot;To it, 

 of all animals,&quot; wrote Herodotus, &quot;nature has not given a 

 tongue.&quot; The power of swimming is shown by the palmated 

 feet, and by the lateral compression of the tail, which thus acts 

 as a large and powerful fin ; the tail is no doubt used as a wea 

 pon of defence, being armed with a serrated ridge of strong 

 square scales. The lower jaw is rather longer than the upper, 

 and both are armed with a single row of pointed teeth, the num 

 ber of which does not vary with age, as in other animals. The 

 Crocodiles are all inhabitants of the rivers and fresh waters of 

 warm countries ; but are most abundant in those latitudes which 

 approach nearest to the equinoctial line. Their mode of feed 

 ing is very peculiar. They do not swallow their prey upon 

 seizing it, nor is it ever eaten while fresh ; but the victim is first 

 drowned, and then conveyed to some hole at the edge of the wa 

 ter, where it is suffered to putrify before it is devoured. Their 

 food consists principally of fish, crabs, and such other animals as 

 they can catch. They seem to manifest an affinity to the Tor 

 toises in the coverings of their bodies, being defended, like them, 

 by plates or shields; with this difference, however, that in the 

 Tortoises the plates are compactly united at the edges, while in 

 Crocodiles they are sufficiently far apart to admit the free mo- 

 tion of all parts of the body and limbs. Owing to a peculiarity 

 in the vertebras of the neck, which bear upon each other by 

 means of small false ribs, that render motion sidewise somewhat 

 difficult, these creatures can not turn about with much facility, 



