510 



THE AMERICAN NATURALIST [Vol. LI 



They agree that there is no correlation between the sugar 

 content of a beet and the quantity of seed which is produced, 

 but Harris and Hogensen find a correlation of .308 ± .013 for 

 the relationship between the weight of the seed beet planted and 

 the weight of seed produced, whereas Pritchard. from a number 

 of determinations, concludes that for beets of ordinary size such 

 as are grown for factory use the correlation between root weight, 

 percentage of sugar in roots and quantity of sugar in the seed 

 root on tlie one hand and the number of grams of seed produced 

 by the seed root is sensibly zero. 



Harris and Hogensen find a correlation of about + .399 be- 

 tween heiglit of plant and amount of seed produced, about 

 + .277 between number of stems and weight of seed produced, 

 and about -f- .122 between number of leaves and weight of seed 

 produced. 



Pritchard has shown that there is no correlation between the 



of its progeny. "The application of this fact to sugar breed- 

 ing." says Pritchard. ''is obvious, as extensive selection may be 

 made for freer seed production without danger of sugar de- 

 terioration. :\Ioreover, it aff'ords an opportunity to reverse the 

 order of selection by making the chief elimination in the seed 

 generation and tlnis greatly r(Mln('e the amount of chemical work 



tween the percentage of sugar in the mother beet and the 

 number of days re(iuired for maturing seed is negative, 

 r = — .129 H= .014. f.. the beets with higher sugar content 



