Keim, see Germ.

Kirchner, on development of Volvox, [204].

Kölliker, on nature of spermatozoa, [175];

on embryonic cells, [196].

Lagynus, fission of, [148].

Lamarck, on use and disuse, [83], [84], [303], [387], [391], [421].

Lamellibranchiata, length of life of, [55].

Larvae, length of life of, [15].

Lasius flavus, length of life of, [50];

L. niger, [51].