213 



IGUANID.E. 



214 



surmounted by a keel which does not divide them in the middle, 

 but which extends from their infero-posterior angle to their aupero- 

 posterior angle. In stuffed individuals, the skin of which has been 

 distended, there ia around the scales of the upper part of the body a 

 circle of small grains which recalls in a degree the mode in which the 

 scaly covering of the Varanians is formed. The lower part of the 

 neck is paved with scales, which are smooth and multifaced. There 

 are rhomboidal and imbricated scales on the dewlap. On the other 

 parts of the body are rhomboidal tile-bke scales (entuildes), and those 

 among them which are not carinated are found upon the thighs, the 

 soles of the feet, and the under side of the toes. The inferior region 

 of these is protected by a band of enlarged scutellations which are 

 imbricated, and surmounted with three keels, of which the middle 

 one is weak and the lateral ones very prominent. The upper part of 

 each toe is covered by a single row of scales ; but each side of the 

 lateral parts of the anterior toes has two rows, whilst the external 

 side of the posterior toes has three, making six rows of scales on 

 each anterior toe, and seven on each posterior toe. Besides being 

 imbricated the scales of the tail form vertieillations, or complete rings, 

 which cease to be distinguishable when they reach towards the 

 extremity. 



All the Iguanas have femoral pores, the number of which varies 

 according to the sex, as Messrs. Dnmdril and Bibron suppose ; and they 

 think that the number would in that case be less in the females than 

 in the moles. These pores, which are placed in a single row, are 

 surrounded by small scales disposed as the petals of a flower arc 

 disposed round its disc. 



The Iguana have the upper parts of the body surmounted by a 

 paleaceous crest of some height, which is continuous from the nape to 

 the extremity of the tail. This crest is composed of strongly com- 

 pressed scales, which are pointed and sometimes curved backwards, 

 gradually diminishing in height as the end of the tail is approached. 

 The nostrils are situated on the sides of the muzzle, and very near 

 the extremity ; their aperture is large, and opened in the middle of a 

 large scale, which forms a convex circle around them, and gives them 

 a tubulous appearance. The tympanal membrane extended over the 

 auditory opening is very large and circular. 



The teeth of the Iguana, which have an especial interest on account 

 of their resemblance to those of the extinct Iguanodon [laUANODON], 

 vary according to the ages of individuals ; and Messrs. Dumdril and 

 Bibron state that they are assured that fewer exist in young subjects 

 than in adult individuals. The first twelve or fourteen maxillary 

 teeth, both above and below, are nearly rounded, pointed, and a 

 little arched; all the others are narrow and compressed, with an 

 angular summit, which is very finely dentilated on its edges. They 

 are not, Dr. Buckland observes, lodged in 4i stmct sockets, like the 

 teeth of crocodiles, but fixed along the internal face of the dental 

 bone, to which they adhere by one side of the bony substance of their 

 root. 



Teeth of lyuana. Dr. Buckland. 



There is a double row of small teeth on each aide of the vault of 

 the palates. 



The Iguanas are herbivorous, and indeed the structure of their 

 teeth would lead to the conclusion that herbs formed their staple. 

 Messrs. Dume'ril and Bibron never found anything but leaves and 

 flowers in the stomachs of the individuals which they opened. 

 Mr. Broderip saw a living lyuana about two feet long in a hothouse 

 at Mr. Miller's nursery -gardens near Bristol. It had refused to eat 

 insects and other kinds of animal food, until happening to be near 

 some kidney-bean plants that were in the house for forcing, it began to 

 eat their leaves, and was from that time forth supplied from these 

 plants. Dr. Buckland, who quotes this, states, in addition, that in 

 1828 Sir Edward Belcher found in the island of Isabella swarms of 

 Iguanas that appeared to be omnivorous ; they fed voraciously on the 

 eggs of birds and the intestines of fowls and insects. The Iguanas live 

 a great deal in trees, and will take to the water, swimming with ease. 

 Mr. Broderip saw an Iguana enter and cross a small pond in the 

 Zoological Gardens at the Regent's Park. The fore feet were motion- 

 less during the passage of the animal across the water. Several 

 specimens of these animals have from time to time been in the 

 collection of the Zoological Society in Regent's Park. 



The species of Iguana are found in Mexico, South America, and 

 the Antilles. Some are considered as very delicate food. 



There are only three species admitted by Messrs. Dume'ril and 

 Bibron : 



/. tuberculata is the Common Iguana. This species has been 

 described by a great many names. Thus, Spix, in his work on the 

 'Reptiles of Brazil,' has, under the names of /. irjuamoia, I. viridii, 



I. ccemilea, I. cmarginata, and /. Lophyroides, represented /. tubercv.- 

 lata of Laurenti, L'Iguane Ordinaire d'Amerique of Cuvier, the 

 Common Iguana, at five different epochs of its life. 



The figures will give some idea of this animal, which is yellowish- 

 green below, and above of a green more or less deep, becoming some- 

 times bluish, and at others of a slate colour. In general there are on 

 the sides of the body brown stripes or zigzags edged with yellow. 

 There is frequently a line of the latter colour traced obliquely on the 

 front of the shoulder. Some individuals are sprinkled with brown ; 

 others have the limbs spotted with brown on a black ground. The 

 tail is surrounded with large brown rings, which alternate with others 

 of green or yellowish. Length seldom exceeding five feet. 



It inhabits a great part of South America, and also the Antilles. 



It is considered excellent for the table. Delicatis&wia and eapidis- 

 sima are among the specific names that have been assigned to it. It 

 is not however deemed very wholesome, and is even considered 

 injurious to those who have suffered from certain diseases. 



n, Head and anterior extremity of Iguana tubcrmlata, two-fifths of the natrnal 

 size ; b, hind foot, same size. 



Wagler makes this species the type of his genus Ifypsilophus. 

 We present a synopsis of the other genera and species of this family 

 from the ' British Museum Catalogue :' 

 I. Body compressed, covered with rings of squarish small often keeled 



scales. Perchers. 

 A. Nostril lateral, below the eye-ridge ; toes slender, simple ; back 



not crested ; interparietal plate small. 



a. Throat compressed, toothed in front ; third and fourth toes 

 nearly equal ; eyes prominent. 



