Column 1: Name of plant and feature observed.
Column 2: Plants from a cross with a fresh stock.
Column 3: Intercrossed plants of the same stock.
Column 4: Self-fertilised plants.
Mimulus luteus—the intercrossed plants are derived from a cross between two plants of the 8th self-fertilised generation. The self-fertilised plants belong to the 9th generation: 100 : 4 : 3.
Eschscholtzia californica—the intercrossed and self-fertilised plants belong to the 2nd generation: 100 : 45 : 40.
Dianthus caryophyllus—the intercrossed plants are derived from self-fertilised of the 3rd generation, crossed by intercrossed plants of the 3rd generation. The self-fertilised plants belong to the 4th generation: 100 : 45 : 33.
Petunia violacea—the intercrossed and self-fertilised plants belong to the 5th generation: 100 : 54 : 46.
NB.—In the above cases, excepting in that of Eschscholtzia, the plants derived from a cross with a fresh stock belong on the mother-side to the same stock with the intercrossed and self-fertilised plants, and to the corresponding generation.
These cases show us how greatly superior in innate fertility the seedlings from plants self-fertilised or intercrossed for several generations and then crossed by a fresh stock are, in comparison with the seedlings from plants of the old stock, either intercrossed or self-fertilised for the same number of generations. The three lots of plants in each case were left freely exposed to the visits of insects, and their flowers without doubt were cross-fertilised by them.