DISTINCTIONS IN CULTIVATED BARLEYS. 
29 
very extreme types the use of these variants must rest upon statis- 
tical methods. 
At any place, the product of a variety in the same season is suffi- 
ciently uniform to give a decided indication of the average size of 
the kernel with 100 measurements. The size of the kernel is, how- 
ever, but partially dependent on variety. Table VI gives a summary 
of measurements made upon samples of grain of three varieties of 
barley grown at various points in the United States. In this table 
the columns marked " Greatest " and " Least " have very little sig- 
nificance, but the averages are quite instructive. The variation is 
remarkably uniform. The length and the lateral and dorso-ventral 
diameters of Princess each differ about 0.5 of a millimeter in the 
averages, while the dimensions of Primus each vary 0.4 mm. and 
those of Chevalier II 0.2 mm. It does not necessarily follow that 
Princess is the most variable of the three. This variety was sub- 
jected to more extreme conditions than the other two, and in two 
locations the development was hardly normal. 
Table VI. — Dimension measurements (in millimeters) of 100 kernels of each of 
three varieties of barley. 
Variety and place of production. 
Length. 
Lateral diameter. 
Dorso-ventral diam- 
eter. 
Great- 
est. 
Least. 
Aver- 
age. 
Great- 
est. 
Least. 
Aver- 
age. 
Great- 
est. 
Least. 
Aver- 
age. 
Princess: 
Huntley, Mont, (irrigated) 
Huntley, Mont, (dry land) 
10.0 
9.9 
9.6 
10.2 
9.6 
10.1 
10.4 
9.8 
10.0 
10.5 
10.4 
10.0 
10.0 
9.8 
10.0 
10.2 
10.4 
9.0 
.8.7 
8.8 
9.0 
8.7 
9.1 
8.7 
9.0 
8.9 
9.6 
9.0 
8.3 
9.0 
8.8 
8.2 
8.3 
8.4 
9.3 
9.2 
9.2 
9.5 
9.1 
9.6 
9.6 
9.5 
9.6 
9.9 
9.8 
9.4 
9.6 
9.4 
9.4 
9.5 
9.6 
3.8 
3.4 
3.7 
4.0 
3.7 
4.2 
3.9 
3.8 
3.7 
4.0 
3.9 
3.8 
3.7 
4.0 
4.0 
3.8 
4.0 
3.3 
3.0 
3.1 
3.3 
3.0 
3.4 
3.4 
3.2 
2.9 
3.4 
3.4 
3.1 
3.1 
3.2 
3.3 
3.0 
3.2 
3.6 
3.2 
3.3 
3.7 
3.4 
3.8 
3.7 
3.6 
3.4 
3.8 
3.7 
3.6 
3.5 
3.6 
3.7 
3.5 
3.6 
3.0 
2.5 
2.9 
2.9 
2.5 
3.3 
3.0 
3.2 
2.6 
2.8 
3.0 
2.9 
2.8 
3.2 
3.1 
3.0 
3.0 
2.2 
2.0 
2.2 
2.3 
2.0 
2.5 
2.5 
2.6 
2.2 
2.4 
2.4 
2.2 
2.2 
2.5 
2.5 
2.1 
2.3 
2.7 
2.2 
2.5 
Plainfield, Cal 
2.6 
2.3 
Primus: 
2.9 
St. Paul, Minn ... 
2.8 
2.8 
2.5 
2.6 
2.8 
Chevalier II: 
2.6 
2.6 
Erie, Pa 
2.8 
Plainfield, Cal 
2.8 
St. Paul, Minn 
2.6 
2.7 
Of the three measurements, that of length is obviously the most 
dependable. The actual variation is no greater, and since it is based 
upon a much larger figure it is relatively less. Also, the two diame- 
ters are more affected by ripening conditions than is the length and 
are therefore less serviceable for local distinctions. The length seems 
to be determined by varietal and climatic influences early in the life 
of the plant, while the diameters are dependent upon the quantity 
of starch infiltration at ripening time. This is well illustrated in 
the two samples of Princess from Huntley, Mont., one of which was 
grown by irrigation and one on dry land. The length of the kernels 
