April, 1911.] Occurrence of Apple Blotch in Ohio. 
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formed by the fungus are irregular in shape, varying from a quar- 
ter of an inch to an inch in diameter. However, they may coalesce 
and cover a larger portion of the apple. Not until the final stages 
does the fungus penetrate more than a few millimeters below the 
epidermis where it gives the infected portion a dry pulpy texture. 
Fig. 1. Apple blotch (Phyllosticta solitaria), showing the nature of 
the disease. 
Fig. 2. Pycnida of P. solitaria and sunken areas of infected tissue. 
Fig. 3. A group of Smith’s cider apples showing the typical blotches. 
Fig. 4. Cankers of P. solitaria on apple twigs. - 
At the time the apples are about to be harvested the blotches are 
most prevalent and at this time the pycnidia begin to appear in 
the diseased spots below the epidermis (Fig. 2). They are not 
found in any definite position, but generally they are only seen in 
the older infected tissue at the center. In the mature pycnidia 
are found the one-celled, ovoid, hyaline spores varying somewhat 
but usually 9x6 microns. In certain cases we have transverse 
cracking of the infected areas which is soon followed by a general 
decay. 
