CHAP. IV. 



CROSS WITH A FKESH STOCK. 



101 



those in Pot II. were excluded, for they had been accidentally 

 injured by a fall during transplantation, and one was almost 

 killed. The eight crossed plants weighed 219 ounces, whilst the 

 eight self-fertilised plants weighed only 82 ounces, or as 100 to 37 ; 

 so that the superiority of the former over the latter in weight was 

 great 



The Effects of a Cross with a fresh Stock. Some flowers on a 

 crossed plant of the last or second generation were fertilised, 

 without being castrated, by pollen taken from a plant of the 

 same variety, but not related to my plants, and brought from a 

 nursery garden (whence my seeds originally came) having a dif- 

 ferent soil and aspect. The flowers on the self-fertilised plants 

 of the last or second generation (Table XXIX.) were allowed to 

 fertilise themselves spontaneously under a net, and yielded 

 plenty of seeds. These latter and the crossed seeds, after germi- 

 nating on sand, were planted in pairs on the opposite sides 

 of six large pots, which were kept at first in a cool greenhouse. 

 Early in January their heights were measured to the tips of their 

 leaves. The thirteen crossed plants averaged 13 16 inches in 

 height, and the twelve (for one had died) self-fertilised plants 

 averaged 13 '7 inches, or as 100 to 104; so that the self-fertilised 

 plants exceeded by a little the crossed plants. 



TABLE XXX. 



Weight of Plants after they had formed Heads. 



