SOLUTE DISTRIBUTION AND BEHAVIOR 



243 



Maskell and Mason (1930c) have approached this 

 problem by actually determining concentration gradients 

 between the bark and bolls, some of which were fertilized 

 and others not. The bolls were divided into two samples, 

 ovules and remaining portion. The gains over a 7-day 

 period in dry weight, water, and nitrogen of the ovules 



Table 25. — Grams Dry Weight, Nitrogen, and Water per 100 Bolls 



{From Maskell and Mason) 

 Ovules 



are presented in Table 25, while the progressive changes in 

 sugar and nitrogen concentrations are shown in Fig. 13. 

 From these data it is clear that by the fourth day the 

 fertilized bolls diverged abruptly from the unfertilized, 

 showing an increased rate of absorption of dry matter, 

 nitrogen, and water. Up to the seventh day the sucrose 

 gradient from bark to boll remained fairly constant for 

 both groups, but the gain in carbohydrate was much faster 



