TOL. LXXXIX.] PHILOSOPHICAL TRANSACTIONS. 505 



tirely by the female. In the succeeding spring, however, the difference became 

 extremely obvious; for the plants from them rose with excessive luxuriance, and 

 the colour of their leaves and stems clearly indicated, that they had all exchanged 

 their whiteness for the colour of the male parent : the seeds produced in autumn 

 were dark gray. By introducing the farina of another white variety, or in some 

 instances by simple culture, I found this colour was easily discharged, and a nume- 

 rous variety of new kinds produced, many of which were, in size, and in every 

 other respect, much superior to the original white kind, and grew with excessive 

 luxuriance, some of them attaining the height of more than 12 feet. I had frequent 

 occasion to observe, in this plant, a stronger tendency to produce purple blossoms 

 and coloured seeds, than white ones ; for when I introduced the farina of a purple 

 blossom into a white one, the whole of the seeds in the succeeding year became 

 coloured ; but when I endeavoured to discharge this colour, by reversing the pro- 

 cess, a part only of them afforded plants with white blossoms; this part sometimes 

 occupying one end of the pod, and being at other times irregularly intermixed with 

 those which, when sown, retained their colour. It may perhaps be supposed, that 

 something might depend on the quantity of farina employed; but I never could 

 discover in this, or in any other experiment in which super fee tation did not take 

 place, that the largest or smallest quantity of farina afforded any difference in the 

 effect produced. 



The dissimilarity I observed in the offspring afforded by different kinds of farina, 

 m these experiments, pointed out an easy method of ascertaining whether super- 

 foetation, the existence of which has been admitted among animals, could also take 

 place in the vegetable world. For, as the offspring of a white pea is always white, 

 unless the farina of a coloured kind be introduced into the blossom, and as the 

 colour of the gray one is always transferred to its offspring, though the female be 

 white, it readily occurred, that if the farina of both were mingled, or applied at 

 the same moment, the offspring of each could be easily distinguished. My first 

 experiment was not altogether successful; for the offspring of 5 pods, the whole 

 which escaped the birds, received their colour from the coloured male. There was 

 however a strong resemblance to the other male, in the growth and character of 

 more than one of the plants; and the seeds of several, in the autumn, very closely 

 resembled it in every thing but colour. In this experiment, I used the farina of a 

 white pea, which possessed the. remarkable property of shrivelling excessively when 

 ripe; and in the 2d year I obtained white seeds, from the gray ones above-men- 

 tioned, perfectly similar to it. I am strongly disposed to believe, that the seeds 

 were here of common parentage; but I do not conceive myself to be in possession 

 of facts sufficient to enable me to speak with decision on this question. If however 

 the female afford the first organized atom, and the farina act only as a stimulus, it 

 appears by no means impossible, that the explosion of 2 vesicles of farina, at the 

 same moment, taken from different plants, may afford seeds, as I have supposed, 



vol. xvni. 3 T 



