290 BOTANICAL GAZETTE APRIL 
could find no correlation between this factor and their resistance 
to brown rot. CULPEPPER, FosTER, and CALDWELL (20) made 
detailed analyses of apples infested with Sphaeropsis malorum, and 
found that the rotted fruit had undergone considerable loss in dry 
matter, a loss in alcohol-ether-water-alcohol extractives, an increase 
in protein nitrogen and in protein phosphorus, a transfer of minerals 
from the insoluble to the soluble fraction, a loss in total sugars, 
mostly in the monosaccharides, a decrease in titratable acidity, 
and a marked increase in alcohol. Starch was not affected. 
STEVENS and HAwkKINs (43) adopted a procedure that eluci- 
dates the progressive changes during rotting, by analyzing (1) the 
fresh strawberry fruits, (2) the sound fruit after storage under the 
same condition as the inoculated fruit, and (3) the fruit inoculated 
and rotted by Rhizopus nigricans. These three samples show the 
parallel changes in sound and infected fruit. They found that the 
acids in the sound fruits decreased, probably due to respiration, 
and that the acids decreased to a less extent inthe rotted fruit. 
The authors believed this to be due to an interference with the 
tissue respiration by the fungus and not to the production of 
ammonia. Sucrose, reducing sugars, and dry matter decreased 
more rapidly in infected than in sound fruit. The fungus causes 
the tissue to soften and to become watery, but whether this is due 
to the death of the cells or to an anesthetic effect is still an open 
question. STEVENS and Morse (44) reported that in the end rot 
of cranberries there is a marked decrease in sugars, while the 
proximate constituents remain fairly constant. The protein, fiber, 
and ash, however, show such relative increases as would be expected 
from the loss of dry matter by respiration. Grpprncs (22) and 
RUSSELL (40) reported the inauguration of studies on apple leaves 
and on potato tubers, respectively, to determine the chemical 
basis of resistance, but they offer no conclusions as yet. 
Recently several papers have appeared which deal with the 
nitrogen distribution of diseased plant tissues, and which promise 
to furnish a new line of attack on these problems. BONCQUET 
(10, 11), working with the mosaic disease of tobacco, Streptococcus 
solani on potato, and B. morulans on beet leaves, reported that 
nitrites and ammonia were invariably found in diseased but never 
