On Germinal Selection as a Source of Definite Variation

by August Weismann

BIOLOGICAL PUBLICATIONS.

THE PRIMARY FACTORS OF ORGANIC EVOLUTION.

By Prof. E. D. Cope. Cuts, 121. Pp., xvi, 547. Cl., $2.00 (10s.).

DARWIN AND AFTER DARWIN. An Exposition of the Darwinian

Theory and a Discussion of Post-Darwinian Questions.

By George John Romanes, LL. D., F. R. S., etc.

1. The Darwinian Theory. With portrait of Darwin.

Pp., 460. Cuts, 125. Second edition. Cloth, $2.00.

2. Post-Darwinian Questions. Heredity and Utility.

With portrait of Romanes. Pp., 338. Cloth, $1.50.