3fl8 IMPREGNATION OF THE SEED. CHAP. VII. 



experiment was obvious. The plants rose with 

 great luxuriance, indicating in their stem, leaves, 

 and fruit, the influence of this artificial impreg- 

 nation ; the seeds produced were of a dark grey, 

 By impregnating the flowers of this variety with 

 the pollen of others, the colour was agairi changed, 

 and new varieties obtained superior in every respect 

 to the original on which the experiment was first 

 made, and attaining, in some cases, to a height of 

 more than twelve feet. In these experiments it 

 was observed that the plant had a stronger tendency 

 to produce coloured blossoms and seeds than white 

 ones. For when the pollen of a coloured blossom 

 was introduced into a white one, the whole of the 

 future seeds were coloured. But when the pollen of 

 a white blossom was introduced into a coloured 

 one, the whole of the future seeds were not 

 white. * 

 Superfc. Mr. Knight thinks his experiments on this sub- 



tation. 



ject afford examples of superfetation, a phenomenon 

 the existence of which has been admitted amongst 

 animals, but of which the proof amongst vegetables 

 is not yet quite satisfactory. Of one species of 

 superfetatiou Mr. Knight has certainly produced 

 examples ; that is, when, by impregnating a white 

 Pea blossom with the pollen both of a white and 

 grey Pea, white and grey seeds were obtained, 

 But of the other species of superfetation in which 

 one seed is supposed to be the joint issue of two 

 * Phil. Trans. 



