148 REPORT OF THE CONFERENCE ON GENETICS, 
Mr. Robert Fenn, V.M.H.: I think that planting the single stock in 
conjunction with the double stock gives a predominance of the double 
stock from the single variety. 
Mr. Arthur Sutton, V.M.H., said that the question of single stocks 
giving double flowers was an intensely interesting ove. He would say 
no more about stocks then than that he did not think there was anything 
in the suggestion of Mr. Fenn. There must be something absolutely 
inherent in the strain. He very much hoped that Miss Saunders would 
be able to eludicate the mystery. 
Mr. Alexander Dean, V.M.H., said that some years ago the matter was 
fought out in the pages of the “Gardiners’ Chronicle.” There was .a 
belief, in regard to Ten-week and Pyramidal stocks, that if the roots were 
examined it would be found that the roots of the doubles were cramped 
or crosswise, and that the single flowers were borne upon the tap-rooted 
plants. That, again, he had reason to believe, was another fallacy. Some 
years ago he had a very fine strain of Scarlet Brompton stocks, but 
ultimately they both became so recessive as to be absolutely white, and 
though he tried to get back the double form he failed to do so, and to-day 
the true old Brompton stock was not commonly to be met with. Mr. 
Sutton might have told them whether Ten-week and Pyramidal stocks 
formed a large proportion of doubles. He believed that it was the case 
that the seeds were produced under glass-house cultivation, and that the 
seeds were starved. 
Mr. Sutton said that to produce the largest possible percentage of 
doubles the plants must be grown in pots. Why, he could not tell. 
M. Maurice de Vilmorin observed that the only thing he could say 
was that it seemed characteristic of the individual, which varies so much.’ 
If out of the same lot of double stocks they found a certain proportion 
of plants to give single flowers, and they grew the seeds of those plants, 
they would find the same proportion of doubles in all. The only way 
was to select the genealogy of the families which gaye doubles.” 
Mr. Dippe said it was heredity in the families of the stocks that some 
plants were inclined to give a higher percentage of doubles, and so by a 
selection they could retain the plants which gave the highest per- 
centage. He did not think by any possibility they could know it from 
the plant. It had been said that there should be a difference in the 
length of the pod. He did not know if that was right, and he had 
not yet finished his examination. It might be possible to tell by the 
pod. Stocks in Germany were grown in pots as well as in the open 
ground. That was done in case of failure through storms. The plants 
were stronger in the open ground than when they were protected from the 
weather under glass. 
The President: It is most interesting to get information first hand on 
this subject. I do not know whether selecting seeds according to size 
gives any result. 
M. de Vilmorin: No. 
Mr. Fenn: It appears to me that the short pod gives more doubles, 
and that it would be better to use seeds from the shortest pods. 
Mr. Dippe: The only way would appear to be to choose those flowers 
which produce doubles, and to throw the others away. 
