THE THREE CONDITIONS OF THE SEED 



33 



the seeds of plants like Arenaria peploides, Vicia sepium. Iris 

 Pseudacorus, etc., which under normal circumstances enter into 

 the typical resting state, it is possible, by keeping the soft, 

 uncontracted pre-resting seed in warm, moist conditions, to 

 induce germination, thus dispensing altogether with the 

 shrinking and resting stages. 



Before making further reference to the ratios for the Neither the 

 shrinking and swelling of seeds, it should be pointed out p^e?resting 

 that as a rule neither the full-grown, uncontracted pre-resting sled^"°'^n^^ 

 seeds nor the resting seeds swollen and ready for germination forgermina- 



c . -n 1 1 ji • 1 • tion are in 



are in a state or saturation. Both markedly increase their a state of 



weight when placed in water. The distinction between the ^**"™*'°"' 



amount of water required for germination and the larger 



amount needed for saturation is dealt with in a later page 



of this chapter. Here I will more particularly allude to 



the behaviour of the soft pre-resting seed in this respect. 



According to the principle that the swelling seed gains what 



the shrinking seed loses, we should infer that the behaviour 



of the large pre-resting seed and of the swollen seed on the 



eve of germination would be the same. This proves to be 



the case. 



When in Jamaica, I found that full-sized soft seeds from 

 the moist green pods of Guilandina honducella gained about 

 20 per cent, in weight when placed in water ; whilst, in the 

 failures of my germination experiments, when the seeds were 

 kept in wet moss, the weight of the swollen seed was often 

 correspondingly in excess of the normal weight for germination. 

 So in England with seeds of Faba vulgaris (Broad Bean) and 

 Phaseolus multiflorus (Scarlet-runner), I obtained similar results. 

 Here, full-grown soft seeds from the green pod, that is to say, 

 seeds that had not yet begun to shrink, added at least lo per 

 cent, to their weight after lying in water for half a day. Then, 

 again, resting seeds of Faha vidgaris^ that under ordinary con- 

 ditions would have germinated when their weight had increased 

 by 90 or 100 per cent., did not germinate at all when allowed 

 to rernain in water, but kept adding to their weight by 



3 



