558 ' FAMILY IGUANIDJS ; IGUANODON ; ANOLIS. 



which these animals feed. They are arboreal in their habits, 

 and feed principally upon vegetable aliment ; it appears, however, 

 that they will sometimes eat eggs, or other animal substances. 

 Their disposition is rather fierce, and they will defend themselves 

 with vigour ; when water is near, they betake themselves to it, 

 and swim with considerable rapidity, by the lateral strokes of 

 the tail. Many of them, indeed, seem to be semiaquatic in their 

 habits, and one singular species, the Amblyrhynchus cristatus, 

 inhabiting the Galapagos Islands, lives principally in the sea, 

 and is never seen to go further on land than the rocks of the 

 coast. The colour of the Iguanas is usually a mixture of green 

 and brown, adapted to conceal them during their residence in 

 trees ; and their hues seem to have some of that power of change, 

 which is so remarkable in the Chameleons. The usual length 

 of the common Iguana is from four to six feet, including the 

 tail. The flesh is very palatable, and is much esteemed in the 

 West Indies as an article of food ; the animals, however, are 

 now becoming scarce in most of the islands. Remains of a gi- 

 gantic Saurian have been discovered in the South East of Eng- 

 land ; which appears, from the structure of the teeth, to have 

 been undoubtedly allied to the Iguanas of the present day ; and 

 which has received the name of Iguanodon. This animal could 

 not have been less than 40 feet in length, and was perhaps more. 

 Its teeth were evidently fitted by the roughness of their sur- 

 face, and by the provision made in the arrangement of the 

 enamel for the continued maintenance of that roughness, not- 

 withstanding the wear of the tooth, to grind down hard veget- 

 able substances to a pulp ; and remains of terrestrial plants have 

 been found associated with it, showing that its habits were nearly 

 the same as those of the existing Iguanas. It is remarkable also 

 that in the structure of the skeleton the Iguanodons and their 

 allies exhibited a most distinct resemblance to the Mammalia, 

 especially to the large Pachyderms. 



495. In this family are also included several other genera ; 

 of which those that have the teeth arranged on the same plan 

 us the Iguanas, are, like them, restricted to the New World. 

 The Anolis is a small, slender, active little animal ; frequenting 



