422 Ever-sporting Varieties 



type was only temporarily lost, but bound to 

 return as soon as new trials are made. 



This wide range of variability between def- 

 inite limits is coupled with a high degree of 

 sensibility and adequateness to the most di- 

 verging experiments. Our tricotylous double 

 races are perhaps more sensitive to selection 

 than any other variety, and equally dependent 

 on outer circumstances. Here, however, I will 

 limit myself to a discussion of the former point. 



In the second generation after the isolation of 

 stray tricotylous seedlings the average con- 

 dition of the race is usually reached, but only 

 by some of the strongest individuals, and if we 

 continue the race, sowing or planting only from 

 their offspring, the next generation will show 

 the ordinary type of variability, going upwards 

 in some and downwards in other instances. 

 With the Phacelia and the mercury and some 

 others I had the good luck in this one generation 

 to reach as high as nearly 90;^ of tricotyl- 

 ous seedlings, a figure indicating that the 

 normal dicotylous type had already become 

 rare in the race. In other cases 80^ or 

 nearly 80^ was easily attained. Any further 

 divergence from the average would have re- 

 quired very much larger sowings, the effect of 

 selection between a limited number of parents 

 being only to retain the high degree once 



