SCIENTIFIC COMMITTEE, APRIL 25. 



lxvii 



productiveness, and that this makes selection possible and desirable. 

 I cannot think that Professor de Vries would for a moment include 

 potatoes as roots in this connection, and without a precise reference to 

 De Vries' work I cannot verify the quotation. Though the several plants 

 in a corn or root crop are all separate individuals, as De Vries says, it is 

 entirely otherwise with potatoes. In the case of potatoes, we all know 

 that, if the crop is not mixed, only one ' individual ' is represented in a 

 crop, even if the field should be 50 or 100 acres in extent. Each plant is 

 but a portion, in a semi-dormant state, of the plant which flourished in 

 the previous season, and no selection in the world can make the plants of 

 one year vary or differ from those of the previous year, of which they are 

 integral parts. This can be proved by anyone who can devote the 

 necessary time and ground to careful experiments, but I am aware that 

 there is a common prejudice against this very obvious fact. 



" Had Professor de Vries been speaking of the selection of potatoes he 

 would of course have referred us, not to a crop of any one variety, each 

 plant the same as the other, but to the 'nursery-bed' where the seedling 

 plants were first raised from seed. It is here, and here alone, that we 

 can say truly that a crop of potatoes ' consists of individuals of varying 

 vitality and productiveness.' It is here alone that selection can be and 

 is usefully employed by potato-raisers, and during the following years 

 when the ' individuals ' in groups, propagated directly from the original 

 seedling plant, are grown side by side for the purpose of eliminating the 

 least promising and retaining only those which are superior to others. 

 Any selection after the first year is of course applied, not to single 

 tubers nor to single plants, but to the several groups of plants represent- 

 ing each original seedling. 



" It has been stated that the selection of small tubers for planting leads 

 prematurely to deterioration, but provided each tuber be fully matured, 

 the size of the 1 set ' planted does not greatly affect the crop, although 

 the result of long- continued experiments points to medium-sized 'sets,' 

 uncut, as giving the best return. 



" The fact that some varieties produce seed very readily and others do 

 not has been referred to as a possible explanation of deterioration ; but 

 the 1 Ashleaf ' is one which produces seed-berries quite as freely as any 

 other variety, and it is the leading example of a potato which shows little 

 or no deterioration. 



" The method of storing ' seed potatoes ' during the winter certainly 

 has great influence on the succeeding crop. 1 Sets ' which are allowed to 

 shrivel and exhaust themselves by throwing out long sprouts, which are 

 rubbed off before planting, are naturally greatly inferior to those which 

 have been well kept from the time of raising the crop in the previous 

 autumn. 



" Deterioration can certainly be postponed by a frequent change of seed 

 from another district, and experience points to Scotland as the source 

 from which such a change of seed is likely to give the best result. The 

 reason why this is so has not been fully shown. It is thought by many 

 that the moister and cooler soils of Scotland prolong the period of growth, 

 and thus prevent premature ripening of the tubers. It is very interesting 

 to note that even in Forres, N.B., Mr. Fraser obtains the best results by 



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