Some flowers on the self-fertilised plants in Pot 4 in Table 3/19 were fertilised with their own pollen, and plants of the eighth self-fertilised generation were thus raised, merely to serve as parents in the following experiment. Several flowers on these plants were allowed to fertilise themselves spontaneously (insects being of course excluded), and the plants raised from these seeds formed the ninth self-fertilised generation; they consisted wholly of the tall white variety with crimson blotches. Other flowers on the same plants of the eighth self-fertilised generation were crossed with pollen taken from another plant of the same lot; so that the seedlings thus raised were the offspring of eight previous generations of self-fertilisation with an intercross in the last generation; these I will call the INTERCROSSED PLANTS. Lastly, other flowers on the same plants of the eighth self-fertilised generation were crossed with pollen taken from plants which had been raised from seed procured from a garden at Chelsea. The Chelsea plants bore yellow flowers blotched with red, but differed in no other respect. They had been grown out of doors, whilst mine had been cultivated in pots in the greenhouse for the last eight generations, and in a different kind of soil. The seedlings raised from this cross with a wholly different stock may be called the CHELSEA-CROSSED. The three lots of seeds thus obtained were allowed to germinate on bare sand; and whenever a seed in all three lots, or in only two, germinated at the same time, they were planted in pots superficially divided into three or two compartments. The remaining seeds, whether or not in a state of germination, were thickly sown in three divisions in a large pot, 10, in Table 3/20. When the plants had grown to their full height they were measured, as shown in Table 3/20; but only the three tallest plants in each of the three divisions in Pot 10 were measured. TABLE 3/20. Mimulus luteus. Heights of Plants in inches: Column 1: Number (Name) of Pot. Column 2: Plants from Self-fertilised Plants of the Eighth Generation crossed by Chelsea Plants. Column 3: Plants from an intercross between the Plants of the Eighth Self-fertilised Generation. Column 4: Self-fertilised Plants of the Ninth Generation from Plants of the Eighth Self-fertilised Generation. Pot 1 : 30 7/8 : 14 : 9 4/8. Pot 1 : 28 3/8 : 13 6/8 : 10 5/8. Pot 1 : -- : 13 7/8 : 10. Pot 2 : 20 6/8 : 11 4/8 : 11 6/8. Pot 2 : 22 2/8 : 12 : 12 3/8. Pot 2 : -- : 9 1/8 : --. Pot 3 : 23 6/8 : 12 2/8 : 8 5/8. Pot 3 : 24 1/8 : -- : 11 4/8. Pot 3 : 25 6/8 : -- : 6 7/8. Pot 4 : 22 5/8 : 9 2/8 : 4. Pot 4 : 22 : 8 1/8 : 13 3/8. Pot 4 : 17 : -- : 11. Pot 5 : 22 3/8 : 9 : 4 4/8. Pot 5 : 19 5/8 : 11 : 13. Pot 5 : 23 4/8 : -- : 13 4/8.