Column 2:  Seedlings from Plants Crossed during the two previous
Generations.

Column 3:  Seedlings from Plants Self-fertilised during many previous
Generations.

Pot 1 :  72 4/8 :  57 4/8. 
Pot 1 :  71 :  67. 
Pot 1 :  52 2/8 :  56 2/8.

Pot 2 :  81 4/8 :  66 2/8. 
Pot 2 :  45 2/8 :  38 7/8. 
Pot 2 :  55 :  46.

Total :  377.50 :  331.86.

The average height of the six crossed plants is here 62.91, and that of the six self-fertilised 55.31 inches; or as 100 to 88.  There was not much difference in the fertility of the two lots; the crossed plants having produced in the greenhouse thirty-five pods, and the self-fertilised thirty-two pods.

Seeds were saved from the self-fertilised flowers on these two lots of plants, for the sake of ascertaining whether the seedlings thus raised would inherit any difference in growth or vigour.  It must therefore be understood that both lots in the following trial are plants of self-fertilised parentage; but that in the one lot the plants were the children of plants which had been crossed during two previous generations, having been before that self-fertilised for many generations; and that in the other lot they were the children of plants which had not been crossed for very many previous generations.  The seeds germinated on sand and were planted in pairs on the opposite sides of four pots.  They were measured, when fully grown, with the following result:—­

Table 5/56.  Lathyrus odoratus.

Heights of plants measured in inches.

Column 1:  Number (Name) of Pot.

Column 2:  Self-fertilised Plants from Crossed Plants.

Column 3:  Self-fertilised Plants from Self-fertilised Plants.

Pot 1 :  72 :  65. 
Pot 1 :  72 :  61 4/8.

Pot 2 :  58 :  64. 
Pot 2 :  68 :  68 2/8. 
Pot 2 :  72 4/8 :  56 4/8.

Pot 3 :  81 :  60 2/8.

Pot 4 :  77 4/8 :  76 4/8.

Total :  501 :  452.

The average height of the seven self-fertilised plants, the offspring of crossed plants, is 71.57, and that of the seven self-fertilised plants, the offspring of self-fertilised plants, is 64.57; or as 100 to 90.  The self-fertilised plants from the self-fertilised produced rather more pods—­namely, thirty-six—­than the self-fertilised plants from the crossed, for these produced only thirty-one pods.

A few seeds of the same two lots were sown in the opposite corners of a large box in which a Brugmansia had long been growing, and in which the soil was so exhausted that seeds of Ipomoea purpurea would hardly vegetate; yet the two plants of the sweet-pea which were raised flourished well.  For a long time the self-fertilised plant from the self-fertilised beat the self-fertilised plant from the crossed plant; the former flowered first, and was at one time 77 1/2