398 



Journal of Agricultural Research 



Vol. XIX, No. 9 



grown under irrigation and was watered sufficiently often to insure a 

 satisfactory growth. In 191 6, only one sample was taken per day, and 

 no samples were taken on Sunday. In 191 7, samples were taken morn- 

 ing and evening, on Sundays as well as on week days; and the series 

 is thus more nearly complete than in the previous year. 



DAILY INCREMENT OF VOLUME 



The data on the daily increment of volume, as shown by the increased 

 length, lateral diameter, dorsoventral diameter, and wet weight of kernels^ 

 fall into two classes, which will be treated separately. The measurements 



S>0 



so 





aif9^f>i>vAzaf^>iinv /j'3-^^G'yff& /& /^ /^ /(^ yt^y^ /O' yT' y^ y(ff.£tyjyj?^ £^J.it*^SJ^e■ 



,yiyy.f^ys'y<s a 9 /£> yy yj' y^ y-^y^/fffy^y,ff ysJVjy^^^^.af^s.^s^y',e»j^jo3y 'T''^ s ■*» 



^yc/^.)^ysy7- ys yg'y^ yffy.»^ia>^y^^^s2*^^S4?G^7,^e^3Jos/ y> ^ <! s s y s s /o 



Fig. 3. — Graph showing maximum and mean daily temperatures recorded at Aberdeen, Idaho, from 

 July 8 to August 4, 1916 (broken line), and from July 15 to August 10, 1918 (solid line). In both years 

 these temperatures are for 36 days following flowering of Hannchen barley. 



of volume are observations immediately obtainable in the field and will 

 be first reported. The chemical constituents of the kernels are deter- 

 mined in the laboratory and will be referred to later. 



Table I shows the weights and measurements of the individual ker- 

 nels on one side of each spike in the samples. The samples were taken 

 at approximately 6 a. m. and 7 p. m. These hours marked the begin- 

 ning and the end of effective sunshine. The morning samples on each 

 date are on the left half of the table and evening samples on the right 

 half. The florets are numbered from the base of the spike toward the 

 tip, so that the figures in each column represent a spike with the base 

 toward the top of the page. In the earlier samples where three spikes 

 were taken, the record of one spike has been omitted from this table 

 because of lack of space. While the number of data makes it difficult 



