572 THE WONDERS OF GEOLOGY. Lect. V. 



whole of the secondary and earlier tertiary epochs. As 

 the living crocodilians frequent fresh water, the remains of 

 animals of this type indicate the existence of countries 

 watered by streams and rivers, or abounding in Jakes : but 

 the modification of the spinal column, so prevalent in the 

 ancient forms, may, perhaps, be referable to a marine, rather 

 than to a terrestrial condition, in some of these extinct saurians. 



26. Enalio-saurians, or marine Lizards.* — Ichthyo- 

 saurus {Fish-like Lizard). — In the Lias of the west of 

 England, teeth, vertebras, and other parts of the skeletons of 

 reptiles, which were supposed to be related to the Crocodiles, 

 had for many years excited attention ; but until 1814, when 

 a considerable collection, from Dorsetshire, formed by Mary 

 Anning, was sold in London, no accurate investigation of 

 these interesting relics had been attempted. f Subsequently 

 a great number of skeletons have been found, numerous 

 memoirs published, and the form and structure of the 

 originals thoroughly investigated. Many beautiful speci- 

 mens are figured and described in the splendid work of Mr. 

 Hawkins, whose unrivalled collection of these remains is 

 now deposited in the British Museum. J The bones of 

 reptiles so abundant in the Lias are chiefly referable to two 

 genera ; the one called Ichthyosaurus (by Mr. Konig), to 

 denote its relation to fishes and reptiles ; the other, Plesio- 

 saurus (so named by Mr. Conybeare), to indicate its nearer 

 approach to the Lizards, or Saurians, than the animals of 

 the other genus. 



The Ichthyosaurus had the beak of a porpoise, the teeth 

 of a crocodile, the head and sternum of a lizard, the paddles 

 of a cetacean, and the vertebra? of a fish. This restoration 

 (Lifjn. 127) shows its general configuration, as demonstra- 



* Medals, p. 708. 



t See No. I. of the "London Geological and Talreontological 

 Journal," for an account of the sale of this collection. 



t Memoirs of Ichthyosauri and riesiosauri; by Thomas Hawkins. 

 Esq. F.U.S. Folio, with 28 Plates. 



