Life Areas of North America: A Study in the Distribution of Animals and Plants. By Dr. C. Hart Merriam, Chief of the Biological Survey, U. S. Department of Agriculture.
Age, Growth, Sex, and Death. By Professor Charles S. Minot, Harvard Medical School.
Bacteria. Dr. J. H. Gladstone.
History of Botany. Professor A. H. Green.
Planetary Motion. G. W. Hill.
Infection and Immunity. Geo. M. Sternberg, Surgeon-General U.S.A.