124 



STUDIES IN SEEDS AND FRUITS 



The effect of 

 depriving a 

 permeable 

 seed of its 

 coverings. 



The effect of baring a permeable seed has been already 

 referred to in Chapter IV in the instance of Canavalia 

 ensiformis. Since the kernel is placed in hygrometric relations 

 with the atmosphere by its porous coats, one would not look 

 for any marked result with seeds that have completed the 

 drying process. ' Indeed, the immediate effect on a seed that 

 has reached a stable weight is merely to give a rather freer 

 play to its hygroscopicity. There is, as one would expect, no 

 attempt to permanently increase its weight. The contrary is, 

 in fact, the case with a seed that has yet water to yield to the 

 air, since the drying process is accelerated by the removal of 

 its coverings. The contrast between permeable and imper- 

 meable seeds in this respect is well exhibited in those plants 

 producing both types capable of being readily distinguished by 

 the eye, as shown in the results below tabulated. 



I made a large number of observations on the effect of 

 baring the kernels of permeable completely air-dry seeds, on 

 the results of which are based the above general conclusions. 

 As examples . of permeable seeds which merely continue to 

 behave hygroscopically on the removal of their coverings, 

 though often in an increased degree, the following may be 

 cited : — 



Achras Sapota (Sapodilla) 

 Anona muricata (Sour-sop) 

 „ palustris 



„ reticulata (Custard Apple) 

 „ squamosa (Sweet-sop) 

 Canavalia ensiformis 



