2 
Harris, A quantitative study of the factors influencing etc. 
The analytical methods employed are those of the modern 
higher statistics, which are steadily gaining ground as tools of 
research. No other technique known to me is capable of attacking 
the kind of problem with which we have to deal. 
The present section deals solely with the interrelationships 
between the characters of the pod and the weight of the seed. 
It touches on no factors except those peculiar to the fruits in which 
the seeds are borne — the pods drawn from a „general population“ 
produced by the cnltivation linder ordinary garden or fielet con- 
ditions of a reasonably homogeneons variety. Thus the material 
has no experimental artificiality. We are, in fact, studying the 
physiology of seed development as it normally goes forward. Fac¬ 
tors which for the present are left entirely out of account will be 
taken up in detail later. 
II. Presentation and analysis of data. 
The portion of the data discussed here consists of five series 
derived from several hundreds of plants, and comprising altogether 
23,312 individually weighed seeds. These will be referred to 
hereafter by key letters. They are: 
L. Golden Wax. Grown at Lawrence, Kansas, 1906. 2861 seeds. 
LL. Golden Wax. Plants the offspring of the L. series. Grown 
at Lawrence, Kansas, 1907. 3947 seeds. 
GG. Burpee’s Stringless. Grown at the Missouri Botanical 
Garden, 1907. 8364 seeds. 
NH. Navy. Grown near Sharpsburg, Ohio, 1907. 5778 seeds. 
ND. Navy. Another series, grown, under very different con- 
ditions, near Sharpsburg, Ohio, 1907. 2362 seeds. 
The characteristics of these varieties and the cultural con- 
ditions under which they were grown have been or will be de- 
scribed for other purposes elsewhere. The most exact description 
of the pods and of the seeds is furnished by the physical constants 
derivable from the tables of data. 
The Influence of Number of Ovules and of Number of Seeds per Pod. 
The data may be best shown in a series of Condensed tables, 
in Table I. Here, the first column shows the number of ovules 
formed (the denominator) and tbe number of seeds developing (the 
numerator) in the pods considered. The number of seeds weighed 
and the total weight (in working units of .025 grams) of seeds 
produced for each dass of pods is given in the 5 pairs of columns. 1 ) 
x ) From the data in this table, the physical constants (means, Standard 
deviations and coefficients of Variation) for ovules per pod, seeds per pod. 
ovules failing to develop per pod, and seed/ovule index can he calculated, as 
well as the rough moments for the correlations between these characters and 
seed weight. The correlations are completed by a knowledge of the Variation 
constants for seed weight by a method explained elsewhere (Amer. Nat. Vol. 44. 
1910. p. 693-699.) 
