Crossed and self-fertilised plants of the second generation.

The crossed and self-fertilised seeds from the crossed and self-fertilised plants of the last generation were sown on opposite sides of two pots; but the seedlings were not thinned enough, so that both lots grew very irregularly, and most of the self-fertilised plants after a time died from being smothered.  My measurements were, therefore, very incomplete.  From the first the crossed seedlings appeared the finest, and when they were on an average, by estimation, 5 inches high, the self-fertilised plants were only 4 inches.  In both pots the crossed plants flowered first.  The two tallest flower-stems on the crossed plants in the two pots were 17 and 16 1/2 inches in height; and the two tallest flower-stems on the self-fertilised plants 10 1/2 and 9 inches; so that their heights were as 100 to 58.  But this ratio, deduced from only two pairs, obviously is not in the least trustworthy, and would not have been given had it not been otherwise supported.  I state in my notes that the crossed plants were very much more luxuriant than their opponents, and seemed to be twice as bulky.  This latter estimate may be believed from the ascertained weights of the two lots in the next generation.  Some flowers on these crossed plants were again crossed with pollen from another plant of the same lot, and some flowers on the self-fertilised plants again self-fertilised; and from the seeds thus obtained the plants of the next generation were raised.

Crossed and self-fertilised plants of the third generation.

The seeds just alluded to were allowed to germinate on bare sand, and were planted in pairs on the opposite sides of four pots.  When the seedlings were in full flower, the tallest stem on each plant was measured to the base of the calyx.  The measurements are given in Table 4/46.  In Pot 1 the crossed and self-fertilised plants flowered at the same time; but in the other three pots the crossed flowered first.  These latter plants also continued flowering much later in the autumn than the self-fertilised.

Table 4/46.  Dianthus caryophyllus (third generation).

Tallest flower-stem on each plant measured in inches.

Column 1:  Number (Name) of Pot.

Column 2:  Crossed Plants.

Column 3:  Self-fertilised Plants.

Pot 1 :  28 6/8 :  30. 
Pot 1 :  27 3/8 :  26.

Pot 2 :  29 :  30 7/8. 
Pot 2 :  29 4/8 :  27 4/8.

Pot 3 :  28 4/8 :  31 6/8. 
Pot 3 :  23 4/8 :  24 5/8.

Pot 4 :  27 :  30. 
Pot 4 :  33 4/8 :  25.

Total :  227.13 :  225.75.

The average height of the eight crossed plants is here 28.39 inches, and of the eight self-fertilised 28.21; or as 100 to 99.  So that there was no difference in height worth speaking of; but in general vigour and luxuriance there was an astonishing difference, as shown by their weights.  After the seed-capsules had been gathered, the eight crossed and the eight self-fertilised plants were cut down and weighed; the former weighed 43 ounces, and the latter only 21 ounces; or as 100 to 49.