Natural History. 37 



Taking an illustration near our own time, we find that, out 

 of the shells in the Norwich Crag at the top of the Pliocene 

 period in the Tertiary age, 85 per cent, exist at the present 

 day ; and yet, between that period and our own lies the whole 

 of the Pleistocene and Glacial age, during which the 

 Mammoth, the cave Bear and the Hyaena, the woolly 

 Rhinoceros, the great Irish Elk and other animals appeared on 

 the scene and passed away, hunted to death for the most part 

 by man. 



It is, however, in the Saurians that the great interest of this 

 period centres. Huge fish-like lizards from 20 to 30 feet long 

 Icthyosaurs with eyes 14 inches in diameter, and Plesiosaurs 

 with long swan-like necks infested the shallower gulfs and 

 bays, some swimming out in the open water and feeding on 

 the fishes and Ammonites, others hiding themselves amongst 

 the tangle and in the crevices of the rocks, and darting out at 

 their passing prey, 



" Dragons of the prime 

 That tare each other in their slime," 



while Pterodactyls large, flying, bat-like lizards, which are 

 principally found in the higher Jurassic strata pursued their 

 victims in the air, and clung to the cliffs and rocks on shore. 

 A strange weird life indeed was that which once filled the 

 plain between Gainsborough and Lincoln, and, with other 

 deposits of the same period elsewhere, it has well been called 

 " the great dragon land." 



This wonderful development of Saurian life began in the 

 Triassic age, attained its greatest energy in the Lias, and 

 finally died out, as a dominating power, in the Chalk. The 

 greater portion of it then passed, by the process of evolution, 

 into birds ; nearly every successive link in the chain having 

 been now discovered, as Professor Huxley remarked at the late 

 meeting of the British Association at Oxford. 



And here, after ascending the Lincoln Cliff and passing 

 over the higher beds of the Lias on our way so well described 

 by Mr. W. D. Carr, whose removal from Lincoln we all 

 deplore as a real loss to our Society we reach the Oolite 

 capping at the top, and stand on ground made famous by many 

 a stirring event in history. Here Caesar's Roman legions 

 came and colonized. Here Norman William reared his 

 fortress against the vain force of Hereward, who lies with his 

 true forsaken wife somewhere in Crowland's precincls amid the 

 fens he kept so well. We from the same site look down, 



