114 



BOTANICAL GAZETTE 



[august 



younger ones; 24 per cent of the 1908 corn had germinated at the 

 end of the experiment; the radicles were short as well as few. 

 Practically 100 per cent of the 191 1 corn germinated and the radicles 

 were long and vigorous. In fig. 6 are given the curves made from 

 the temperature data of table VI. This experiment, in addition to 

 being very clear and striking in its indication of the deterioration 

 which takes place on keeping seed even for the short space of three 

 years, is of special interest because it furnishes a test of the value 

 of commercial seed. 



Experiment V— Hemp seed, from Ames, Iowa, of the crops of 

 1907 and 191 1, and of 1908 and 1910; 5.5 grams of each lot were 



Fig. 6. — Cory corn (sweet) (experiment IV) : 30 grams; broken line, 1908; solid 



line, 191 1. 



washed with concentrated aqueous solution of corrosive sublimate, 

 thoroughly rinsed with boiled distilled water, and soaked for the 

 usual length of time. The experiment with 1907 and 191 1 seed 

 was set up on May 1, that on the 1908 and 19 10 seed on May 13 • 

 191 2. The data are given in table VII. 



It is obvious that, because of the small amount of seed used. 

 namely, 5 . 5 grams, the rise in temperature would be less than when 

 larger quantities were used; but it is interesting and significant that 

 only a small sample need be used to test the quality of seed, pro- 

 vided only that the insulator be a good one. Thus we have a rise 

 of 5?35 C. taking place in the flask containing 191 1 seed, whereas 

 the temperature in the flask containing 1907 seed merely fluctuated 



