210 



STUDIES IN SEEDS AND FRUITS 



The most 



instructive 



arrangement 



of the 



"swelling" 



data. 



The deter- 

 mining 

 influence of 

 permeability. 



ences in this direction, and accordingly I have not burdened 

 my pages with it, though the reader can construct it for him- 

 self from the table subjoined, where all the data are grouped 

 in another fashion. 



In order to wrest their story from all these data, I will make 

 use of another arrangement as given below. Here the seeds 

 are arranged in two columns. In the first column the seeds 

 are placed in order according to the amount of the swelling 

 ratio of the coats, those with the greatest ratio being placed 

 first. In the second they are placed according to the value of 

 the swelling ratio of the kernel, those with the largest ratio 

 coming first. There is nothing definite to be made out of the 

 arrangement of the seeds in the first column, since permeable, 

 variable, and impermeable seeds, whether or not we restrict 

 ourselves to the Leguminosae, are fairly well distributed. On 

 the other hand, if we turn to the second column, which contains 

 the data for eleven impermeable, twenty-one variable, and 

 thirteen permeable seeds, we find that all but one of the im- 

 permeable seeds occur in the upper half of the column, where 

 the swelling ratio for the kernel is the largest, and all but one 

 of the permeable seeds in the lower half, where the ratio is 

 smallest, the variable seeds being about equally distributed. 



We perceive the same contrast between the indications of 

 the two columns when we compare the places occupied by 

 seeds when both permeable and impermeable seeds occur in 

 the same species. Thus with Entada polystachya and Dioclea 

 reflexa^ the permeable and impermeable seeds come close 

 together in the column where the seeds are arranged accord- 

 ing to the amount of the swelling ratio of the coats, but lie far 

 apart when the arrangement chosen, as in the second column, 

 is that of the amount of the swelling ratio of the kernel. 



Evidently, therefore, although the question of permeability 

 or of impermeability is largely shaping itself in its influence on 

 the swelling ratio of seeds, it is an influence that chiefly affects 

 the kernel. The coats also respond, though in a less degree, 

 to this influence, but their behaviour is often masked by 



