G. E. Briggs, F. Kidd, and C. West 111 



Table VIII. — " Pferdezahn" Maize grown at Poppelsdorf in 1875. 



* The figures in brackets in column 5 give the percentage increase in dry-weight for 

 the number of days stated in column 2. 



In forming a clear picture of the growth of the plant as presented by 

 its increase in dry- weight, it is as well to keep in mind the fact that from 

 80 % to 90 % of the dry-weight is the result of the process known as 

 carbon-assimilation and that the actual percentage of the dry- weight of the 

 plant derived from the mineral constituents of the soil is relatively small 

 (cf. Hornberger(6), Monnier(i7), Eabinovitch (20) and others(26, 4, 8 & 3)) 1 . 



1 Jones and Huston(8) give the following figures for the ash of maize at different 

 periods: 



