768 



Journal of Agricultural Research 



Vol. VI, No. 20 



of the seeds of red clover remaining impermeable after 10 days be 

 reckoned as capable of germinating in one year. He later tested in 

 distilled water 66 lots of red-clover seed from various sources, using 

 1,000 seeds of each lot. From 2.4 to 90 per cent of the seeds of the 

 different lots which remained impermeable after 10 days softened in 



f/OOt 



Fig. 



-Curves showing the rate of softening and of germination of impermeable red-clover seeds of 



different lots. 



distilled water in one year. On the basis of these results Nobbe (15) 

 abandoned his previous position as untenable. 



Different lots of seeds of any one of the species of plants included in 

 Table III illustrate differences in the rate of softening of the impermeable 

 seeds which are comparable to those reported by Nobbe. Figure 2 



