164 THE WONDERS OF GEOLOGY. Lect. II. 



rhinoceros, it had small lateral eyes, great lips, and a nasal 

 proboscis. 



Among the reptilian remains are skulls and bones of a 

 Gangetic Crocodile or Gavial, and of a land Turtle, which 

 cannot be distinguished from those of species still living in 

 India. But the most extraordinary discovery is that of 

 bones, and portions of the carapace, of a Tortoise of gigantic 

 dimensions ; it has been aptly named Colossochelys Atlas : 

 the length of this reptile exceeded twelve feet. 



27. The Pampas. — The Pampas, those vast plains in 

 South America, which present a sea of waving grass for 900 

 miles, are principally composed of alluvial loam and sand 

 containing freshwater and marine shells, and were once, 

 like Lewes Levels, a gulf, or arm of the sea. In these alluvial 

 deposits, bones of enormous extinct mammalia have fre- 

 quently been discovered. Towards the close of the last cen- 

 tury, an almost perfect skeleton of a gigantic animal (Mega- 

 therium), was dug up, at a considerable depth, in a bed of 

 clay, on the banks of the river Luxor, about four leagues 

 W.S.W. of Buenos Ayres. This skeleton was sent, in 

 1789, to the museum at Madrid, where it now remains. It 

 is described and figured by Cuvier, under the name of 

 Megatherium. 



In 1832, Sir Woodbine Parish, with considerable labour 

 and expense, collected many bones of a similar creature 

 from the Salado ; having actually diverted for a time the 

 river from its course, that he might disinter these remains ; 

 these he afterwards presented to the Museum of the Royal 

 College of Surgeons of England. 



Since that time relics of several other remarkable forms 

 of extinct mammalia have been discovered ; a few of these 

 we will here briefly describe. 



The Pampas, observes Mr. Darwin, may be regarded as 

 one vast sepulchre of these lost quadrupeds. The deposits 

 in which the bones occur are as follow : — 



