:',6 



due to the increase in totiil ash of the phxnts on the calcareous soils. 

 For uistance, the amount ot lime in the di-y substance of sweet cassava 

 (combined leaves, stalks, and roots) increased in Plats II, III, and 

 IV, while the increase ot lime in the ash was marked in the plants 

 from Plat IV only. There were also moderate increases in the 

 amounts ot lime in the dry substance of sunflowers (combined leaves 

 and stalks) and radishes (leaves and roots) on Plats II, III, and 

 IV. But it should be noted that these increases were of smaller 

 magnitude on the ])lats with 18 per cent and 35 per cent of CaCOg 

 than on the plat with 5 per cent; in fact, on the plat with 35 per cent 

 of CaC03 the combined leaA'es and stalks of simflowers contained 

 little if any more lime than on the check plat. This would seem to 

 point to sunflowers and radishes having a certain regulatoiy power in 

 the absorption of lime from strongly calcareous soils. 



Wliat was true of the effect of tlie calcareous soils on the quan- 

 tity of magnesia in the ash ol the plants holds also for the effect on 

 the cjuantity of magnesia in tne dry substance with slight modi- 

 fications. Bush beans and soy beans showed onl> slight decreases 

 in the quantity of magnesia in the dry substance on Plat IV^. With 

 sunflowers and radishes there were sUght decreases Li the magnesia 

 on Plat III and marked decreases on Plat IV. vSugar cane and sweet 

 cassava on all the calcaieous soils contained slightly more magnesia 

 than on the check soil. 



The quantities of 2>otash and phosphoric acid in the dry substance 

 of the plants did not seem at all affected by the carbonate of lime. 

 As a whole, the results wei'e fairly constant and where variations 

 did occur they were irregular, pointing to neither an increasmg nor 

 de]iressing effect. 



With regard to the amount of silica iji the dry substance there was 

 a marked and significant decease with rice only. 



The regular variations in asli composition and in quantity of the 

 mineral constituents in the dry substance of tlie plants that were 

 induced by the carbonate of lime are summarized below: 



Bush beans. Decrease in Fe^Oj in the ash and dry substance. 



Soy beans. Slight increase in CaO, slight increase in IMgO, and 

 marked decrease in Fe203 in the ash and dry substance. 



Sunflowers (combined analyses of leaves and stalks). Decrease 

 ui MgO and slight decrease in P.Oj in the ash. Sligiit decrease in 

 MgO in the dry substance. 



Radishes (combined analyses of leaves and roots). Small increase 

 in CaO, decrease in ilgO, and marked decrease in Fe;03 in the ash 

 and dry substance. 



Sweet cassava (combined analyses of leaves, stalks, and roots). 

 Increase in CaO, decrease in Fe203 (Plat IV only) in the ash. Increa?© 

 in CaO, slight increase in MgO, slight decrease in Fe.jOg (Plat IV 



