Habits, inheritance of, ii. [395].
Häckel, on cells, ii. [370];
on the double reproduction of medusæ, ii. [384];
on inheritance, ii. [397].
Hackles, peculiarities of, in fowls, i. 254.
Hair, on the face, inheritance of, in man, ii. [4];
peculiar lock of, inherited, ii. [5];
growth of, under stimulation of skin, ii. [326];
homologous variation of, ii. [325];
development of, within the ears and in the brain, ii. [391].