FOSSTL CARNIVORA 27 
and varied, at the dawn of the Age of Mammals, and the different 
kinds become more and more specialized throughout the Eocene 
epoch. Meanwhile the true Carnivores appear in increasing 
numbers and gradually crowd out the Creodonts until the last of 
them has disappeared by the end of the Oligocene epoch. In 
their evolution the different Creodont groups specialized on much 
the same lines of development as those the true Carnivores took 
Eocene 
Basal Lower Middle Upp 
Ws . SAY 
\N 
HY YY 
gb 
GY4Y) 
GG 
BLL 
Ki 
Diagram showing how the true Carnivora crowded out the 
Creodonta or Primitive Carnivora during the Tertiary Period. 
NY Creodonta. GZ, True Carnivora. 
FIG, 8 
afterwards. They were more or less wolf-like, weasel-like, cat- 
like or bear-like, according to the nature of their food and the 
manner of attacking their prey. 
Fossil remains of flesh-eating animals are by no means as 
common as those of Herbivora, and the remains of Creodonts are 
especially rare, and mostly fragmentary. The great majority 
have been found in the Eocene fossil fields of the Western United 
States. This Museum is peculiarly rich in these rare and inter- 
esting fossils. Out of the 113 American species it possesses 
all the known specimens of 50 and the types or other good 
