a 
THE HALL OF FOSSIL VERTEBRATES 
All these series have been placed according to geological age. 
The most ancient specimens, found in the lowest rock-strata, 
and hence representing the earliest stage of evolution, are placed 
first in the series. The most recent ones, found in the upper- 
most rock-strata, and representing the final stage of evolution of 
the race, are placed last. Arranging the species of a race from 
each stratum in the order of the age of the strata, we find that 
they show a regularly progressive change from the most ancient 
to the most recent. At no point in a given series can we draw 
a line and say: This is and that is not, a horse—or a camel—or a 
rhinoceros. The visitor, therefore, can demonstrate for himself 
the evolution of the race of Horses or Camels or Rhinoceroses, 
within certain limits. Of the evolution of Man we have no 
satisfactory illustration from fossils. 
It should be observed that the evolution of a race consists 
mainly in the adaptation of the structure of the animals to par- 
ticular surroundings and habits of life. There is also a universal 
progress in intelligence, the more ancient animals having rela- 
tively smaller brains than their successors. 
ARRANGEMENT OF THE HALL. 
Fosstt MAMMALS. 
On the north side of the hall next the entrance are arranged 
the Amblypods, ancient hoofed animals long ago extinct, unlike 
any living animal, although suggesting elephants, rhinoceroses, 
hippopotami and bears in different parts of the body (skeletons 
of Pantolambda and Coryphodon, skulls of Uintatherium). Next 
to them are the Condylarths, the most ancient of Hoofed Mam- 
mals, chief among them the Phenacodus skeleton, well known to 
students and figured in most geological text-books as the proto- 
type of the Hoofed Mammals. Next to these are the Carnivora, 
or flesh-eating mammals, of which four fine skeletons are placed 
in the large ““A’’-case. Then come the Insectivora, or insect- 
eaters, and Rodents, or gnawers, represented by small and incom- 
plete specimens. Then the Elephants (Mastodon skeleton, skulls 
of mastodons and mammoths) and the various kinds of Artio- 
dactyls, or Cloven-hoofed animals, which are allied to modern 
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