52 SEVENTH REPORT. 



I 

 Killing Solution. Check. Difference. 



Dry material 1.235 grams. .07 grams. -1.165 grams. 



Ash 31.9% 57.12% 25.22% 



Kp 46.2 .36 (?) 



From my study of this subject, the following conclusions were 

 reached : 



1. The amount of acid in dilute solutions of HCl is reduced by grow- 

 ing corn seedlings in them. 



2. The mineral content of radicles killed in n-25G HCl was nearly 

 one-half that of normal radicles. The Potassium and Chlorine were 

 less. 



3. Bacteria and fungi thrived in the solution in which the seedlings 

 were killed. None were perceptable when the seedlings were kept in 

 distilled water for one week. 



4. The seedlings which were killed in n-256 HCl excreted much ma- 

 terial rich in potassium. 



5. Seedlings of corn grown in distilled water excrete potash, or some 

 other alkali. 



The following are suggestions received from my work : 



1. The fact that the amount of acid in solutions in which seedlings 

 are grown becomes reduced, suggests that the death is caused by a 

 chemical action. 



2. The fact that the killed radicles contain less potassium than 

 normal ones, and that the solution in which they were killed is rich 

 in potassium, suggests that death is caused by a chemical action be- 

 tween the acid of the solution and the potassium of the radicle. 



3. The fact that fungi and bacteria grow so vigorously in the solu- 

 tion in which the seedlings were killed, and did not thrive in the dis- 

 tilled water in which seedlings were growing, suggests that the excre- 

 tions or extractions caused by the acid solution might be some organic 

 compound especially nutritious to these lower forms of plant life. 



I am indebted to Professor F. S. Kedzie for most of the chemical 

 analysis involved in this problem. 

 Agricultural College, Mich, 



