THE COLLECTION OF FOSSIL VERTEBRATES 



[5 



or collateral ancestors of the modern Horses, Asses and Zebras, 

 are in one alcove, arranged in series from the most ancient to 

 the most recent. The most ancient and structurally primitive 

 groups of mammals come first, tlie most modem and familiar 

 types come last. 



South (Rioht) Side. 

 fTITANOTHERES 



Chalicothercs 



Pcrissodactyls 



or Odd-Toed 



Hoofi-d 



Mammals 



Tapirs 



Lophiodonts 



RHINOCEROSES 



PaK-cotheres 

 HORSES 



North (Left) Side. 

 AMBLYPODS ) Primitive Hooft-d 

 CONDYLARTHS i Mammals 

 Monkeys, Bats, Rodents, Insectivores 

 and other Small Primitive Mammals 

 Marsupials 



CREODONTS ( Carnivorous 

 CARNIVORES f Mammals 

 Seals, Dolphins, Whales, ) Marine 

 Sirenians etc. i Mammals 



MASTODONS and ) p^ob^.^eideans 



ELEPHANTS » 



ELOTHERES 



Anthraeutheres 



or 



Even-Toed 



Hoofed 



Artiodactvls 



Pigs and Peccaries [^ 

 OREODONTS 



CAMELS 

 DEER etc. 

 Litopterna 

 Toxodontia 

 Typotheria 

 EDENTATA J 



Mammals 



Fossil Mammals 

 Peculiar to South 

 America. 



SOUTH (RIGHT) SIDE. 



The south side of the hall is entirely devoted to the Peris- 

 SODACTYLS or Odd-Tocd Hoofed Mammals in which the number 

 of toes (in the hind foot and generally in the forefoot) is either 

 I, 3 or 5, while in the other main division of hoofed animals, the 

 Artiodactyls, it is either 2 or 4; or more exactly, the axis of 

 symmetry of the foot passes through the central toe in Pcris- 

 sodactyls, while in Artiodactyls it passes between two toes. 



The TiTANOTHERES come first in the series of Perissodactyla, 

 large animals which suggest rhinoceroses in general south Ai- 

 proportions, but have a differently shaped head and 

 peculiar teeth. These began as hornless animals of 

 moderate size (Cases i and 17) and increased in size 

 and developed large bony horns (Cases 3, 5 and 19) before they 



cove I. 



Titan- 



otheres 



