SOUTH AMERICAN 



523 



some occur in Patagonia and Argentina. In these countries 

 extensive and most richly fossiliferous fresh-water deposits are 

 found interstratified with the marine. The succession, so far as 

 known, is as follows : — 



4. Araucanian Series, or Stage. 

 3. Santa-Cruzian Series, or Stage. 

 2. Patagonian Series, or Stage. 



f Subpatagonian Stage. 



I Pyrotherium Beds. 



The Subpatagonian and most of the Patagonian are marine, the 

 others lacustrine. The mammals which are found more abun- 

 dantly than in any other known deposits are, in all but the last 

 of these formations, totally different from those of the northern 

 continents. There are no Artiodactyls, Perissodactyls, Elephants, 



FIG. 169. — ■ Skeleton of Toxodon platense. (Lydekker.) 



or Mastodons, neither Condylarthra nor Amblypoda ; no Car- 

 nivores, Creodonts, Insectivores, or Bats. The very numerous 

 genera of hoofed animals all belong to orders unknown in the 

 north, — Toxodontia (Fig. 169), Typotheria, and Litopterna. 

 There are Monkeys of South American type, and great numbers 

 of Rodents, also South American, belonging exclusively to the 

 Porcupine series (Hystricomorphd) ; no Squirrels, Marmots, Bea- 

 vers, Mice, or Rabbits occur among them. A marvellous number 

 of Edentates, Sloths, Armadillos, and Ant-eaters are found ; and, 

 most remarkable of all, numerous Australian types of Marsupials, 

 both herbivorous and carnivorous, are a characteristic feature. 



