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COMPLICATIONS ARISING IN THE CROSS-BREEDING OF STOCKS. 149 
Miss Saunders: I quite agree with what has been said. We must 
regard the suggestion of planting double stocks in proximity to single 
ones as merely a fairy tale. The double stock is absolutely sterile and 
can have no effect whatever upon a neighbouring plant. If we are to 
get any further with this question we must breed from individuals. I 
have been breeding from individuals, and have kept families distinct for 
some time. I quite agree that there are certain individuals which give 
a large percentage of doubles, and certainly there are also individuals 
from which one cannot get a double. I cannot find a red glabrous 
Ten-week stock that does not throw a double. I have white and cream 
glabrous belonging to the same strain, and some of them will give 
doubles. and some will not. It is undoubtedly a question of individuals. 
I have chiefly grown stocks in the open ground because I was aware of 
the belief that the production of doubles was increased by starvation. 
One fact is extremely interesting in regard to cress-breeding. If you 
cross a glabrous Ten-week stock with an individual which produces 
doubles, in F, you get the Mendelian proportions between singles and 
doubles. Whether or not the doubling is effected by environment, there 
appears to be a certain regularity. The general result of the crossing of 
two individuals which are proved to be self-fertilising and are not 
throwing doubles, will be that you will not get doubles. If neither is 
throwing doubles you cannot get doubles in a later generation. 
Mr. Fenn: If the bee works in the double stock, what is it for? I 
think the double stock must give pollen. 
Miss Saunders: He is not looking for pollen, because there is none. 
The President: Perhaps the bee goes to try. 
Mr. Fenn: I have seen bees work in the double and then work 
directly in the single. I think the bee must go for pollen. 
Miss Saunders: That is an assumption which, in the face of all our 
observation, would require very definite proof. Has anyone ever found 
a single grain of pollen in a double stock ? 
