238 Report oF THE HortTICULTURAL DEPARTMENT OF THE 
storage by correspondence with a number of the leading apple 
storage men of the State brought out the fact that they had but 
little to fear from storing russeted fruit. But a similar investi- 
gation among retailers showed that such fruit was not wanted 
because it kept poorly when exposed to the air or in a dry 
atmosphere. 
The following brief description of the microscopic characters 
of the russeted epidermis of an apple enables one to see why 
shriveling and decay set in more quickly with injured than with 
sound apples. 
MICROSCOPIC CHARACTERS OF RORDEAUX INJURY ON FRUIT. 
A study of the structure of the skin of the apple shows that 
this heavy outer covering is composed of comparatively large cells 
whose outer walls are thick, strong and cutinized.% Over these 
outer cutinized membranes is the cuticle proper. Outside of this 
cuticle we have still further, with many varieties, a coating of a 
bluish white, waxy substance, the bloom. On still other varieties, 
or with all of the russet apples, there is here and there, or covering 
the whole surface of the fruit, a yellow-brown or gray-brown 
1ough, corky condition of the cuter part of the epidermis. The 
number of layers of cells in the epidermis of an apple seems to 
vary from two to five or more. The cells of the fruit flesh, directly 
underneath the epidermis, are small, flattened by tangential stretch- 
ing, and have comparatively thick walls. ‘Toward the center of 
the fruit the cells increase in size and their walls become thinner 
and soon they become large, true, flesh cells with nearly equal. 
diameters. 
A comparison of the epidermis of a bordeaux-injured apple with 
that of a healthy one shows that the waxy covering, the cuticle 
proper, and many of the cells of the epidermal layers have been 
destroyed. (Plate XX.) Such epidermal cells as remain, and 
those of the fruit flesh which are injured, have much thickened 
walls, of a brown, corky appearance. The more severe the injury, 
the thicker this corky condition. In some cases it is very superficial, 
involving, as nearly as can. be ascertained, but one or two cell 
layers; in other cases, four, six, eight and sometimes ten layers of 
cells are destroyed. No attempt was made to ascertain whether 
the cell injuries are of a physiological or of a mechanical nature, 
this field of investigation belonging more properly to others; bit 
* Tschokke (61). 
