104 



STUDIES IN SEEDS AND FRUITS 



Contrast be- 

 tween the 

 permeable 



and imper- 



to contend in acquiring impermeability. Though no doubt 

 exceptional in this particular case, they indicate the character 

 of the obstacles under certain climatic conditions. 



The contrast in appearance and in behaviour under different 

 tests between the permeable seed of Dioclea reflexa where the 

 shrinking process has been prematurely arrested, and the im- 

 permeable seed of the same plant where it has been normally 

 completed, is very striking. The first is brownish black, and 

 its coats bend, but do not Crack, in the hand-vice. The second 

 is much lighter in colour, often mottled, and its coats are 

 relatively brittle. The kernel of the impermeable seed is dry 

 and almost friable, whilst that of the permeable seed is moist in 

 appearance and compact in texture. As shown in the tabulated 

 comparison subjoined, the greatest contrast is presented in the 

 water-contents and in the capacity of absorbing moisture from 

 the air after being heated. I may remark here that the behaviour 

 of the bared kernels during the four hours that passed before 

 they were placed in the oven was very significant, that of the 

 impermeable seed gaining nearly 3 per cent, in weight, and that 

 of the permeable seed losing rather over 3 per cent. 



COMPARISON OF AN IMPERMEABLE AND A PERMEABLE SEED OF DIOCLEA 

 REFLEXA FRESH FROM THE FORESTS OF THE GRAND ETANG IN 

 GRENADA, AND WEIGHING RESPECTIVELY 83*5 AND 83*1 GRAINS. 

 BOTH THE COATS AND THE KERNEL WERE EXPOSED TO A TEM- 

 PERATURE OF 100-105 C. FOR i HOURS. (Results are stated as 

 percentages.) 





Note, The behaviour of the separate coats and kernel is essentially the same, and 

 differs only in degree. 



