1000 



HISTORICAL GEOLOGY. 



Claw of Megalonyx Jeffersonii (x ; 



Gigantic Edentates, species related to the Sloth and Armadillo, of the 

 genera Megatherium, Mylodon, Megalonyx, Glyptodon, and others were also 

 in the Korth American fauna, although most characteristic of South America. 

 Their remains have been found at Natchez in Mississippi, in Florida, and in 

 Georgia, South Carolina, Texas, Kentucky, Oregon, and elsewhere. 



Remains of the Megatherium mirabile of Leidy were found in Georgia, 

 at Skiddaway Island, and in South Carolina. Megalonyx is another genus of 



these large Sloth- 

 1^*^^- like animals. Its 



species occur over 

 the Pampas of 

 South America, to 

 the Straits of Ma- 

 gellan ; but the first 

 known was found in 

 Virginia, in Green- 

 brier Count}-, and 

 was named Megalo- 

 nyx by Jefferson, in 

 allusion to its large 

 claws (Fig. 1560). Its bones have also been found at Big-Bone Lick, Ky.^ 

 and elsewhere. 



A North American Mylodon, M. Harlani, has been found both east and 

 west of the Mississippi, and in Oregon. 



Rodents were represented by the gigantic Castoroides Ohioensis, related 

 to the Beaver {Castor Canadensis). The Beaver has a length, exclusive of 

 the tail, of about three feet ; the Castoroides was nearly or quite five feet 

 long. Its remains have been found in New York, Ohio, and south to 

 Mississippi (Natchez). 



The Peccary, Dicotyles nasutus, has been found near Squankum, N. J., 

 and in Virginia. 



Among Carnivores, a Lion, Felis atrox, from Natchez, was about as large 

 as that of Britain. There were also Bears, as the Ursus amplidens of 

 Leidy, from the same locality, and the Arctotherium simum of Cope, from 

 Shasta County, Cal. 



The Equus beds of Marsh (1877) are deposits of Pleistocene Mammals, 

 occurring over various parts of western North America, from Mexico and 

 Texas to Oregon and western Nebraska. It has been questioned whether 

 they were not of later Pliocene age. Many have afforded remains of four 

 species of Equus, Elephas primigenius. Mastodon, Megatheridce, Glyptodon, 

 MacJicerodus {Smilodon) , and other kinds. 



The marine species of the St. Lawrence and the borders of Canada and 

 New England, in contrast with the terrestrial, were cold-water species, 

 and show that the Straits of Belle Isle, between Newfoundland and Labrador, 

 were very widely opened by the subsidence of the Champlain period. 



