Pterocles, European Miocene, 161
Pterodon, European Eocene, 125
Pupa, Eocene, 169
Pupa vetusta, Palæozoic, 169
Pythonidæ, European Miocene, 165
R.
Racoon-dog of N. China, 226
Rana, European Miocene, 166
Region, the best term for the primary zoological divisions, 68
Arctic, why not adopted, 69