880 Journal of Agricultural Research vol. xx, no. h 



It is readily observed that considerably more of each of these elements 

 was utilized by the seedlings grown in garden soil than by those grown 

 in distilled water. This would seem to indicate either that the distilled 

 water is deleterious to the growth of seedlings grown in it or that some- 

 thing needed in the process of translocation was accessible when the 

 beans were grown in soil but not when they were grown in distilled water. 



Distilled water even of the highest purity has been considered toxic 

 to seedlings grown in it, because of the difference between the osmotic 

 pressure within the root cells and that of the distilled water surrounding 

 them. The distilled water used in these experiments was obtained from 

 a Barnstead automatic water still and contained traces of copper and 

 calcium. In this case the toxic effect of the copper, if any could be 

 attributed to it, was counteracted by the calcium, as there was no 

 evidence of the characteristic poisonous effect of copper on the roots. 



It is hoped that more light may be thrown on the subject of the utili- 

 zation of the mineral constituents in the cotyledons by the young plant 

 under varying conditions by experiments now in progress in this 



laboratory. 



SUMMARY 



When beans were grown in soil, a notably larger amount of reserve 

 material was translocated from the cotyledons than when they were 

 grown in distilled water. 



In both cases, a smaller proportion of calcium was translocated than 

 of phosphorus or magnesium. 



