29 
feet -in length. Their bones are so common in many places in 
the South as to be used by farmers for building fences. 
The earliest mammals of the period, those of Eocene age, are 
illustrated by specimens and casts of fossils from the Paris basin. 
The mammals of the White River beds of South Dakota of 
miocene age are illustrated by teeth, skulls and other bones of 
Oreodon, Mesohippus, Elotherium, Dinictis, etc. The Oreodon, 
whose skulls occur in great abundance in the Bad Lands of South 
Dakota may be described as “a ruminating hog” since it com- 
bined character of the hogs and ruminants. It was probably 
about the size of a sheep. 
The Elotherium was also a large hog-like animal of active 
habits. An exceptionally fine skull is shown. 
Skull of Titanotheriiim tichoceras a different species from 
that shown in Hall 35- 
Vertebrate fossils of the miocene beds of the Sewalik Hills, 
India, are represented by numerous casts. 
Cast of skull and limb bones of Diprotodon a huge, ancient 
kangaroo. 
Case 13 B. — Fossils of the Quaternary Period. Invertebrates 
are illustrated by large shells of ostrea or oyster, now extinct, 
from North Carolina. Also by numerous specimens from Quar- 
ternary clays of Europe. 
Among vertebrates should be noted the series of teeth of the 
Mammoth and Mastodon, Teeth of the Mammoth are shown 
from Texas, Idaho, San Salvador and Alaska. These indicate 
the wide range of this animal. 
Note the great number of cross ridges in the teeth of the 
Mammoth and the tubercular surface of the teeth of the Masto- 
don. The latter indicate that the movement of the jaw of the 
Mastodon was vertical like that of carnivores, rather than lateral, 
like that of herbivores in general. 
Limb bones and hair of the Mammoth from Alaska and 
Siberia. Limb bones and teeth of hippopotamus and bison from 
England showing that these animals lived in England in compar- 
atively recent times. Limb bones and casts of eggs of Euryp- 
teryx, and Mesopteryx and others of the huge birds which inhabited 
New Zealand until very recent times. 
Skull of Ursus spelaeus or cave bear. This was a bear of 
