42 FIRST REPORT ON ECONOMIC BIOLOGY. 



The above line of treatment must be followed for at least two 

 seasons." 



APPLE SCAB or " BLACK SPOT." 



Venturia inequalis, Aderhold. 



This, and the allied disease attacking pears, is at the present 

 time rampant throughout Worcestershire, and in a less degree in the 

 remaining six Midland counties. 



FIG. 20. APPLE AND PEAR SCAB. 



