Helianthus A unit us Syncotylcus. 471 
a value of 19% a race with values ranging between 50 c /o 
and 89/c arose immediately, and that this value was 
fairly constantly maintained under continued selection. 
Some low values (25-50% ) still occurred in the first 
two generations which followed the original plant of 
1887, but they have not occurred since. The highest 
values attained in the various years deviate but little ; 
the deviations lying well within the probable error of 
observation, or due to occasional differences between the 
climates of the succeeding years. The hereditary values 
of the parents selected each year were as follows : 
HARVEST OF 1887 1888 1889 1890 1891 1892 1894 1895 1896 
Values of the parent ig gg gl 94 g? gg SQ Q3 82 
plants in percentages 
In some years the parent was not the individual which 
possessed the highest value. This was due to the fact 
that when the differences in the values are small it mav 
tf 
be necessary to pay attention to other circumstances also 
and especially to reject weak individuals, or such as 
flower too late, or set little seed, or happen to be fas- 
ciated. 
The choice of a parent must further be left to chance 
in groups of equally good plants with practically the 
same hereditary values ; because sunflowers are too large 
to permit of diminishing the elements of chance by dou- 
bling the principle of the selection by the application of 
the method of selection by grandparents (see p. 385); 
but, as it happened, I was mostly fortunate in my choice, 
with the exception of the last year in which the mean 
sank from SS% to about 68%. 
My race is not to be regarded as a normal eversport- 
ing variety but as an improved breed within it. Instead 
of selecting parents with SQ-90 c /r and over I could have 
