FATE OF SEEDS INDICATED BY BALANCE 229 



however, only possible when kept in a dry room. A 

 punctured seed in nature would soon fall a victim to the 

 attacks of mould and insects, unless it germinated quickly. 



The failures amongst the impermeable seeds are, as one The failures 

 might expect, very instructive. We can trace the slow LwrseeT" 

 progress of the loss of impermeability in seeds fathered bv areinstruc- 



ir 11T1 r ^^^^ "^ P''^- 



ourselves trom the plant. In the course or an experiment senting-per- 



covering years, a single seed in a sample gradually begins ^quaiif/by 



to fail, a change unerringly indicated in the balance by the '^^'^"•*- 



increase of weight. Two seeds of Entada scandens^ the 



shrinking process of which I had watched after collecting them 



in the immature, uncontracted state, preserved their weight 



unchanged for a few weeks, and then began slowly to gain 



weight, until at the end of a year each had added 3 per 



cent, to its weight. After this they behaved hygroscopically, 



like ordinary permeable seeds. The explanation was supplied 



in the development of fine cracks in the cuticle. In another 



case three seeds, also of Entada scandens^ which together 



weighed 1080 grains, gained i grain during the first year. 



By subsequently weighing them separately the culprit was 



discovered, two of the seeds remaining quite unchanged in 



weight. The cause of failure in one of the seeds lay in an 



imperfection of the cuticle. The same thing occurred during 



an experiment on six seeds of Guilandina bonducella weighing 



in all about 200 grains. A gain in weight of i per cent. 



during the first year led me to weigh them separately, and it 



was thus discovered that this increase was due entirely to one 



seed, which on close inspection showed defects in the outer 



coat. 



The above experiences of faulty impermeable seeds show 

 that nature fails at times in endowing a seed with imperme- 

 ability, but the suggestive implication is that in such failures 

 permeability is presented to us as a quality by default. 



Although the indications supplied by my numerous Prof. Ewart 

 experiments seem clear and unmistakable with reference to the °he imperme- 

 ultimate fate of the impermeable seed, the views held by ^'''^ ^^^^- 



