Chap. IV. 



CROSS WITH A FRESH 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 ivith 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. 



