380 FOSSIL REPTILES. 



far the most abundant among the existing iguanas. The 

 cornuta of St. Domingo is like the common species in magni- 

 tude, colours, and general forms ; but upon the front of the 

 head, between the eyes and nostrils, are found four large and 

 scaly tubercles. Behind them rises an osseous and conical 

 horn, which is enveloped by a single scale. The fossil horn of 

 which we have been speaking was, beyond all question, a de- 

 pendency of this description. There were even found upon 

 its surface impressions of the tegument by which, in all pro- 

 bability, it was connected with the cranium. 



We shall now close this description of the reptile inhabitants 

 of the ancient world, by a quotation from a book to which the 

 author of this imperfect sketch of fossil remains has been most 

 deeply indebted, and to which he will always be both ready 

 and proud to acknowledge the extent of his obligations. The 

 Baron Cuvier thus expresses himself in the conclusion of his 

 immortal work on the '' Ossemens Fossiles :" — 



" It will be impossible in future not to recognize as an esta- 

 blished truth, the multitude, the magnitude, and the surprising 

 variety of the reptiles which inhabited the seas, or which covered 

 the surface of the globe, at that ancient epocha in which the 

 strata were deposited, commonly designated by the too restricted 

 appellation of the formation of Jura. Also, that they inhabited 

 immense tracts of territory, where not only man had no exist- 

 ence, but where, if there were any of the mammiferous tribes, 

 they were so very rare, that not above a fragment or two can be 

 cited as authentic. 



*' This variety, this magnitude, and this number, are still 

 further announced, independently of the undetermined pieces 

 of which I have spoken in the article on the megalosaurus, by 

 many of those collected by Mr. Conybeare, and which, at first, 

 he imagined to belong to the plesiosaurus, but which do not 

 find their representations in the skeleton of Lyme. 



" In his second memoir, for example, pi. XXL, is seen 

 a portion of a lower jaw, and a bone which appears to me to 



