102 HETEEOSTYLED DIMORPHIC PLANTS. Chap. IIL) 



of fruit, but the fruits themselves yielded a slightly 

 lower average number of seeds than did the long-styled 

 plants. The results of Hildebrand's experiments on 

 the fertility of the two forms are given in the follow- 

 ing table : — 



Table 19. 

 Pulmonaria officinalis (from Hildebrand). 



In the summer of 1864, before I had heard of Hilde- 

 brand's experiments, I noticed some long-styled plants 

 of this species (named for me by Dr. Hooker) growing 

 by themselves in a garden in Surrey; and to my sur- 

 prise about half the flowers had set fruit, several of 

 which contained 2, and one contained even 3 seeds. 

 These seeds were sown in my garden, and eleven 

 seedlings thus raised, all of which proved long-styled, 

 in accordance with the usual rule in such eases. Two 

 years afterwards the plants were left uncovered, no 

 other plant of the same genus growing in my garden, 

 and the flowers were visited by many bees. They set 

 an abundance of seeds ; for instance, I gathered from a 

 single plant rather less than half of the seeds which it 

 had produced, and they numbered 47. Therefore this 



