296 BOTANICAL GAZETTE [APRIL 
characters. The susceptible varieties show more abundant aerial 
growth of both sorts than do the resistant. Possibly the amount 
of surface growth is dependent on the vigor of the subsurface 
growth, and the latter is no doubt less in the resistant varieties 
(figs. 1, 2). 
Another varietal characteristic was the relative firmness of the 
rotted fruit. The sound fruit of the resistant varieties was some- 
what more firm than that of the susceptible, particularly in the 
ripe stage. After rotting, the differences were even more marked. 
Although this fungus causes what is usually called a firm rot, the 
rotted fruit of the C and SCF varieties was almost watery in some 
instances; while the resistant varieties maintained a firm or even 
hard texture. This phenomenon may have to do with the character 
of the pectins, as has been suggested by others. The pectin rela- 
tions of hosts and parasites offer a fruitful field of investigation (53). 
Chemical analyses 
Instead of presenting the analytical results in tabular form, 
which would be rather involved and cumbersome, they are given 
in the form of charts (figs. 3-7). The data could conceivably be 
grouped in many different ways, so as to show (1) the comparison 
of the fresh fruit of the several varieties; (2) the progressive changes 
during the ripening process; (3) the changes involved during 
storage in the laboratory, both with and without the action of the 
fungus; and (4) the effect of the rotting process. This would mean 
four different groupings of the data in four sets of charts. It was 
decided to limit this to two groupings. The first set, figs. 3 and 4, 
bring together side by side the data showing the change in composi- 
tion of the samples during the storage and rotting in the laboratory. 
The fresh samples in each case are designated a, the sound samples 
stored in the laboratory without inoculation b, the rotted samples ¢. 
In these charts it is easy to follow the changes brought about by the 
rotting, and the changes taking place during the three stages of 
growth, by comparing all the a samples, the 6 samples, and the ¢ 
samples in each variety. 
The second set, figs. 5-7, bring together side by side the data 
for comparing the various varieties, that is, the a samples for all 
