192 



M. M. McCooL 



by the addition of distilled water. After thirty days the experiments 

 were discontinued. The results obtained appear in Table 10: 



TABLE 10. Experiment Continued for Thirty Days 

 (The data observed for five plants were calculated for ten plants, so that a comparison 

 might be made with other experiments) 



Composition of solution 



Total 

 weight 

 of tops 



(grams) 



Total 

 weight 

 of roots 

 (grams) 



Average 

 length 

 of tops 

 (centi- 

 meters) 



Remarks 



N/25MnCl2 (a) 



(b) 

 N/50 MnCl^ (a) 



Too dry 

 to weigh 

 7.0 

 8.5 

 9.0 

 10.0 

 5.0 

 5.6 

 9.2 

 9.8 

 8.0 

 6.4 

 8.1 



3.2 



2.3 



12.2 



10.0 



9,0 



5.4 

 4.1 



8.2 

 8.6 



10.2 

 7.8 



10.0 



6 

 9 



24 

 22 



27 

 29 

 18 

 20 

 28 

 25 

 26 

 25 

 28 



Tops dead 



Leaves slightly chlorotic 



(b) 

 Distilled water (a) 



Color good 



(b) 

 N/25 CaCl2+N/25 MnCh. (a) 



(b) 

 N/50 CaCl2+N/50 MnCU. (a) 



(b) 

 N/25 CaCh (a) 



Color fair 

 Color fair 

 Color good 



(b) 

 N/50 CaCh (a) 



Color good 



(b) 





Fig. 14. — Ajiiidotal relations between calcium and manjanese in soil cultures 



1. N/50 CaCb 4. N/25 MnCb 



2. N/.50 CaCl2-fN/50 UnCh 5. N/25 MnCh -t-N/25:CaCl2 



3. N/50 MnClz 6. N/25 CaCh 



7. Distilled water 



