464 Notices of Memoirs—Prof. Boyd Dawkins’s Adiress. 
dealing with the fossils, and especially of the later rocks, is that 
which is offered by the fauna and flora of the geographical province 
in which they are found. The non-recognition of this principle 
has led to serious confusion. The fauna, for example, of the Upper 
Sivalik Formation has been very generally viewed from the European 
standpoint, and placed in the Miocene, while, judged by the stand- 
point of India, it is really Pliocene. A similar confusion has followed 
from taking the Miocene flora of Switzerland as a standard for the 
Tertiary flora of the whole of the Northern Hemisphere. 
It now remains for us to see how these principles may be applied 
to the co-ordination of Tertiary strata in various parts of the world. 
In 1880 I proposed a classification of the European Tertiaries, in 
which, apart from the special characteristic fossils of each group, 
stress was laid on the gradual approximation of various groups to the 
living Mammalia. The definitions are the following :— 
DIvistons. 
1. Eocene, or that in which the higher 
Mammals (Eutheria) now on the earth were 
represented by allied forms belonging to existing 
orders and families. 
Oligocene. 
CHARACTERISTICS. 
Extinct orders. 
Living orders and families. 
No living genera. 
2. Miocene, in which the alliance between 
fossil and living Mammals is closer than before. 
Living genera. 
No living species. 
3. Pliocene, in which living species of Mam- 
mals appear. 
4. Pleistocene, in which living species of 
Mammals preponderate, 
Living species few. 
Extinct species predominant, 
Living species abundant. 
Extinct species present. 
Man present. 
5. Prehistoric, or that period outside history 
in which Man has multiplied exceedingly on 
the earth and introduced the domestic animals. 
6. Historic, in which the events are recorded 
in history. 
These definitions are of more than European significance. 
Man abundant. 
Domestic animals present. 
Wild Mammals in retreat. 
One extinct Mammal. 
Records. 
The 
researches of Leidy, Marsh and Cope prove that they apply equally 
to the Tertiary strata of North America. The Wasatch Bridger and 
Uinta strata contain representatives of the orders Cheiroptera and 
Insectivora, the suborders Artio- and Perissodactyla, and the families 
Vespertilionide and Tapiride ; but no living genera.’ The Mam- 
malia are obviously in the same stage of evolution as in the Hocenes 
of Europe, although there are but few genera, and no species com- 
mon to the two. 
1 The genus Vesperugo has not been satisfactorily determined. Cope, Report of 
Geological Survey of the Territories, Tertiary Vertebrata, vol. i. 1884. 
