Chap. II. CROSSED AND SELF-FERTILISED PLANTS. 3? 



self-fertilised ones, having become unhealthy towards the close 

 of their growth, and they were severely attacked by aphides. 

 From this cause nothing can be inferred with respect to their 

 relative fertility. In this generation we have the first instance 

 of a self-fertilised plant in Pot II. exceeding (though only by 

 half an inch) its crossed opponent. This victory was fairly won 

 after a long struggle. At first the self-fertilised plant was several 

 inches taller than its opponent, but when the latter was 4i 

 feet high it had grown equal ; it then grew a little taller than 

 the self-fertilised plant, but was ultimately beaten by it to the 

 extent of half an inch, as shown in the table. I was so much 

 surprised at this case that I saved the self-fertilised seeds of 

 this plant, which I will call the " Hero," and experimented on 

 its descendants, as will hereafter be described. 



Besides the plants included in Table VII., nine crossed and 

 nine self-fertilised plants of the same lot were raised in two 

 other pots, IV. and V. These pots had been kept in the hot- 

 house, but from want of room were, whilst the plants were 

 young, suddenly moved during very cold weather into the 

 coldest part of the greenhouse. They all suffered greatly, and 

 never quite recovered. After a fortnight only two of the nine 

 self-fertilised seedlings were alive, whilst seven of the crossed 

 survived. The tallest of these latter plants when measured was 

 47 inches in height, whilst the tallest of the two surviving self- 

 fertilised plants was only 32 inches. Here again we see how much 

 more vigorous the crossed plants are than the self-fertilised. 



Crossed and self-fertilised Plants of the Seventh Generation.* 

 These were raised as heretofore with the following result : 



Table VIII. {Seventh Generation.) 



