absorption of Mirabilis vulgaris by M. longiflora, ii. [88];

crosses of species of Verbascum, ii. [93], [107];

on the hollyhock, ii. [107];

crossing varieties of tobacco, ii. [108];

benefits of crossing plants, ii. [130], [131], [175]-[176];

self-impotence in Verbascum, ii. [136], [141];

effects of conditions of growth upon fertility in Mirabilis, ii. [164];

great development of tubers in hybrid plants, ii. [172];

inheritance of plasticity, ii. [241];

variability of hybrids of Mirabilis, ii. [265];