IGUANAS. Ill 



found swarms of them which he had reason to consider omnivorous, 

 feeding voraciously on birds' eggs and the intestines of birds and 

 insects. 



The Common Iguana (7. tuberculata, Fig. 27), which inhabits a 

 great part of South America, is one of the best known of this family. 

 These Reptiles are easily recognised from the large pouch underneath 

 the neck, and the dentated crest which extends from the head to the 

 extremity of the tail. The tail, feet, and body are covered with small 

 scales. On the upper part their colour is a more or less decided 

 green, sometimes becoming blue, at others slate-coloured ; the lower 

 part is of a yellowish green. The sides present zigzag, roundish, 

 brown scales, edged with yellow ; frequently a yellow line is traced 

 obliquely in front of the shoulder, and some specimens are sprinkled 

 with brown ; others have the limbs spotted with brown on a black 

 ground. The tail is surrounded with brownish rays alternating with 

 others of green and yellow. When full grown it attains the length of 

 four feet, but the more ordinary length of the animal is about thirty 

 inches. They are very gentle creatures, and perfectly harmless, 

 feeding almost exclusively on vegetables. They are hunted for their 

 flesh, which is excellent; and they are most numerous in Surinam 

 and Brazil. 



[Of a kindred species, Metopoceros cornutus, which is common in 

 the Antilles, an excellent description has been published by Lieu- 

 tenant Tyler,* which we must endeavour to condense. This Reptile 

 attains a length of five, and sometimes even six feet, the tail being 

 about twice and three-quarters the length of the body. When first 

 hatched it measures four inches. The mouth is large, and is armed 

 with two rows of maxillary and two of palatal teeth, which appear 

 simply to be intended to crop grass and to provide the stomach with 

 vegetable food. Each maxillary tooth is a little double-edged saw, 

 and they are so lapped over each other that the reptile, in closing its 

 mouth upon a leaf, cuts through it completely. The tongue is curi- 

 ously used by the animal to draw food into the mouth, and to forward 

 it down the gullet, or to repel it at will, and the only use of the palatal 

 teeth appears to be to secure the food while the tongue moves forward 

 to afford fresh assistance in its journey down the throat. The tongue 

 is always covered by a glutinous secretion, the gland which secretes 

 it being perceptible when the mouth is open. Between the lower jaw 

 and the chest is a pouch, which the animal draws in or extends simul- 

 taneously with the compression or swelling out of the body when 



* " Proceedings of the Zoological Society" for 1850, p. 106. 



