LONGEVITY OF SUBMEliGEI) SEEDS 337 



less than seven years, and then subjected in their supposcdly 

 supersaturated condition, to two sharp freezes. Whether othei- 

 species kept their vitahty through the seven years' submergence 

 and were killed by the frost can not be known. 



Thus, while the experiment did not fully reach the goal which 

 was planned, the question suggested by the vegetation on the 

 bed of the drained pond has received a partial answer. Nearly 

 half of the species whose seeds were used in the longer experiment 

 gave some germinations after a submergence of more than four 

 years and at least three species or 13.6% of those used in the 

 experunent were still represented by viable seeds at the end 

 of seven years' continuous submergence. Consequently it may 

 be inferred that no such strain is placed upon the efficiency of 

 the various distributing agents as was involved in the suggestion 

 that the seeds which germinated in the bed of the drained pond 

 must have been transported thither in the course of a few months" 

 time at longest. 



