THE IGUANA. 271 



the third class — reptiles, of the vertcbrated sub-kingdom. It is generally 

 from four to five feet long; the greater part of this great length, however, 

 i-i made up by the tail, which is something more than half of the reptile. 

 The head, in comparison with the usual size in Saurians, is short; at the 

 junction with the neck it is large and full, and is of greater measurement 

 from its top to the under part of the throat, while from a point taken from 

 its summit, the jaws incline towards the muzzle at an angle of fifty, making 

 the head of the Iguana upon the whole shorter, higher, and more symmetrical 

 than that of either the Alligator or of any other species of its own family. 

 The body is long and slender, without any greater roundness at any one point 

 than at another. It is supported on four legs of considerable length; the 

 fore ones are somewhat shorter than the hind ones, and its toes are not 

 long, nor are the claws attached to them of any length, but those of the 

 hinder legs are very long, with the claws corresponding: there is an apposable 

 toe on the feet, l^he tail of the Iguana is exceedingly firm and wiry, and 

 is possessed of a strong elastic power. The skin is of a firm tough texture, 

 and is covered with small thick scales; its colour when the Iguana is young 

 is a beautiful light green, but when it is at its full growth it is usually of 

 a pale green, with a slight shade of yellow. 



The principal mark of distinction in the Iguana and the Iguana family 

 is the crest and dewlap with which it is provided. From the back part 

 of the head rises a crest of strong cartilaginous substance, which runs 

 along the back from that point to the seat of the hinder legs. A pretty 

 correct idea of this may be conveyed by comparing it to the sharp side 

 of a saw; the exception, however, must be made in this, that the small 

 spears or excrescences of the crest are not so much in the shape of an equilateral 

 triangle, nor do they stand so closely together, as the teeth of the saw. 

 The dewlap hangs from the beginning of the throat to the seat of the fore 

 legs. This is composed of a strong membraneous substance. In the '^Iguana" 

 proper it seems to be for ornament solely, but in some other species it is 

 capable of being distended by the reptile, and no doubt serves some purpose 

 or other in the procuring of its food. These two ornaments vary in size 

 according to the gender of the Iguana. In the male they are much larger, 

 and the crest especially is more formidable than in the female. 



In the line of generalization the Iguana seems to form the link between 

 the Alligator and the other creeping things whose habits and existence are 

 entirely terrestrial. In the scale of descent in the vertebrated kingdom, 

 the Iguana, it would appear, stands next to the Alligator, and seems to 

 be the continuation of the important class of reptiles from the water to 

 the land; for it is to be observed that, whereas the Crocodile and the 

 individuals of that family, although, strictly speaking, amphibious, do pass 

 the whole of their lifetime in the water, the Iguana, on the contrary, 

 which is also possessed of the power of living in both elements, passes the 

 greater part of its existence on land, and resorts to the water only occasionally, 



