98 STUDIES ON APPLES. 



BOUGH (NOT ILLUSTRATED). 



The apples of this variety ripen so rapidly that the time necessary 

 to bring- them from the orchards gave considerable opportunity for 

 marked changes to occur before the specimens reached the laboratory. 



The apples used were obtained from two orchards, one in Delaware 

 and the other at Geneva, N. Y. In both cases the samples had reached 

 an advanced stage of ripening before they arrived at the laboratory. 

 Those arriving from Geneva, August 24, showed the, starch to be 

 nearly gone from within the core line only a little remaining near 

 the carpel seams. Outside this line a slight tendency to streak was 

 becoming evident. 



In the specimens arriving one week later, on August 31, the starch 

 within the core limit had entirely disappeared. Outside the core line 

 strong streaking had occurred; at each of the V -zones were regions 

 which stained very black with iodin. On September 8 the starch had 

 very much decreased, the greater part appearing in the V-zones. 



Of the several varieties observed the Bough is one of the most strik- 

 ing illustrations of the changes in the quantity of starch in the various 

 zones of the tissues, though the location of the oval zone perhaps is 

 not so well defined as in some others. 



CONCLUSIONS. 



The macroscopic studies on the localization of starch in the process 

 of ripening led to the following conclusions: 



The ripening takes place in two more or less well-defined stages. 

 The first of these occurs within the core line, the second in the torus 

 flesh. The first ordinarily begins by a decrease in the starch content 

 in the tips of the core wedges. This decrease extends outward to the 

 core line, and the last regions within this zone to lose their starch are 

 the fan-shaped portions flanking the carpel seams of the core region. 



The second stage ordinarily sets in somewhat before the first is fully 

 completed, and is usually heralded by starch-\free streaks appearing 

 in the midst of the torus flesh. Though not at all confined to them, 

 the first indication of the disappearance of the starch is commonly 

 most pronounced in the oval zones. These zones increase in size and 

 other radial streaks appear in the fleshy portion until in the middle 

 part of the torus flesh there exists but little starch. Usually, extend- 

 ing outward from the fibrovascular bundles of the carpel ribs and 

 seams, there are fan-shaped (or V-shaped) portions which may best be 

 termed V-zones, and which, together with the peripheral 1.5 to 3 mm 

 of the flesh, are among the last to lose their starch. 



Another fact shown is one well recognized by horticulturists, 

 namely, that summer apples ripen much more irregularly than the 



