April, 1915.] The Inheritance of Size in Tomatoes. 
487 
The fruits of the F-2 series 15-11-2 gave the following average 
weights of fruits: 
15-11-2. Plant 1 = 2.36 
“ “ 3 = 1.76 
“ “ 5 = 3.60 
“ “ 6 = 2.16 
“ “ 7 = 3.00 
grams. 
The average weight of fruits of this series is 2.58 grams. 
These four series of F-2 generation hybrids give a total of 44 
F-2 plants whose average fruit-weights vary from 1.33 grams to 
4.16 grams. The lightest fruit possessed a weight of .38 gram 
while the heaviest fruit weighed 5.63 grams. The variability of 
the F-2 fruits was greater than that of the F-l fruits. The aver¬ 
age fruit-size of the F-2 generation plants agrees fairly well with 
the average of the fruit-size of the parent F-l generation. Dis¬ 
tinct segregation of size characters was noted in the F-2 fruits. 
The following table shows the average fruit-weights of the 
plants of the F-3 generation (17-12-4): 
17-12-4. Plant 1 = 3.25 grams. 
“ “ 4 = 2.40 
“ “ 5 = 2.42 “ 
“ “ 6 = 3 '06 
“ “ 7 = 1.50 
“ “ 8 = 3.46 
“ “ 9 = 2.62 “ 
“ “ 10 = 2.22 “ 
In this generation segregation of size characters of fruit was 
observed. The average weight of fruit for this generation was 
found to be 2.62 grams. The variability and generation average 
are practically the same as in the F-2 fruits. 
From plant 10 of the F-3 series came the seeds which produced 
the plants of the F-4 generation (43-14-2). This generation was 
grown in the garden. The average fruit weights of the different 
plants are as follows: 
43-14-2. Plant 1 = 2.30 grams. 
“ “ 2 = 2.73 
“ “ 3 = 1.94 
“ “ 4 = 1.95 “ 
“ “ 5 = 1.80 
“ “ 6 = 1.74 
“ “ 7 = 2.87 
“ “ 8 = 1.56 
“ “ 9 = 2.03 
“ “ 10 = 2.59 
“ “ 11 = 2.85 
Segregation of size characters of fruit occurred in this F-4 
generation. Both variability and the average size of fruit of the 
generation are somewhat less than in the F-3 fruits. 
