on the duration of life, [7], [10];

on the essential meaning of sexual propagation, [11], [103], [135], [141];

on natural selection as the origin of sexual reproduction, [14];

on Prof. Vines’ criticism, [14], [90], [99], [178] et seq.;

on the Protozoa and natural selection, [15], [102];

on Lamarck, [16];

on adaptive development, [19];

and natural selection, [21];

summary of theory of germ-plasm, [23];

theory of organic evolution, [26], [48], [50], [58], [66], [68], [87], [100], [104], [106-108], [114-115], [147];