92 



STUDIES ON APPLES. 



WEAKENING OF CELL WALLS AND INCREASE OF INTERCELLULAR AIR. 



During the fall of 1901, in the course of the examination of certain 

 varieties, the intercellular air in the flesh of the fruit seemed to 

 increase constantly. This led to the making of some determinations 

 of the specific gravity of apples at different periods. The only tests, 

 however, which were made during the first season's work, were carried 

 out in December. The next summer and autumn a number of esti- 

 mations were made at different stages in the growth and maturity of 

 the fruit, the results showing that the specific gravitj 7 diminishes to 

 the extent of 2 to 5 per cent. The results given, however, are the 

 average specific gravities of from two to four specimens, and toward 

 the latter part of the experiment it became apparent that the results 

 would have possessed more value if a larger number of specimens had 

 been used. In determining this factor the entire apple was used, and 

 hence is not to be considered as representing the exact specific gravity 

 of the flesh, though comparisons niade for the purpose of this work 

 showed that the results were only slightly below that of the flesh when 

 taken alone. The results of this work are tabulated in Table X. 



TABLE X. K/>cciJic yntrity of whole fruit. 



u Picked August 15. 

 b Picked September 15. 

 c Picked September 15-20. 



respiration experiment, cellar temperature, 

 in respiration experiment, cold-storage temperature. 



