192 



SEVENTEENTH REPORT. 



TABLE I. 



The seeds were germinated in sterile test tubes on nutritive agar 

 medium, one seed being placed in each tube ; and the above records 

 were made five days after the seeds were placed in the tubes. The 

 germination took place at room temperature. 



From this table it is readily seen that the mercuric chloride did 

 not hinder the germination of the seeds, but that it greatly cheeks 

 the further development of the young seedlings. I also noted that 

 those seeds treated only with sulfuric acid germinated about twenty 

 hours sooner than the others and had therefore a better start. The 

 ]ilants were left for about a week and some that made only a feeble 

 start continued their growth but only feebly. Not enough data is 

 here recorded to make any definite statement upon the jtercentage 

 of sterile seeds but the great majority' are sterile and enough so 

 that I can proceed with my problem unhindered. 



Conclusions. The results which I have obtained in my work on 

 sterilization of pop corn seems sufficient to Avarrant the following 

 conclusions : 



1. That mercuric chloride even at very low concentrations and 

 for short durations of time is toxic to the developing young seedling 

 of pop com. 



2. That sulfuric acid (sp. gr. 1.84) in which the seeds were treat- 

 ed for four minutes is the best disinfectant which I have obtained. 



3. That absolute sterility cannot be obtained because probably 

 there are some fungi and bacteria so deep in the seed coats that 

 they are not reached by the disinfectant. Sterile seeds, however, 

 are obtained in a]>])roximately 90% of the seedlings. 



LITERATURE. 



1. BroAvn. dOOO) Proceed, of the Roy. Soc. London. Vol. 81. 

 Ser. B, p. 82. 



2. deZeeuw. Richard (1911) The Comparative Vitality of Seeds, 



