106 MANUAL OF FRUIT DISEASES 



composed of a thin felt of dark-brown interwoven threads 

 which are seen with the naked eye or better with a hand-lens. 

 Fly-speck (Fig. 29), while formerly regarded as distinct from 

 sooty-blotch, is now considered simply as a different symptom 

 of the same disease. The two are found in the same situations 



and under similar 

 conditions except that 

 fly - speck develops 

 later than sooty- 

 blotch. Fly-speck 

 needs little description 

 (Fig. 29). Groups of 

 a half dozen to one 

 hundred black, shiny 

 dots appear on the 

 surface of an apple; 

 the specks resemble 

 closely those made 

 by the fly (Fig. 29). 

 Both sootv-blotch and 



FIG. 29. Fly-speck. . J 



fly-speck are very 



superficial in nature, and there is no hardening or cracking of 

 the apple skin as in scab. 



Cause. 



The pathogene causing the disease was described on Newtown 

 Pippins from the state of Pennsylvania in 1831. More atten- 

 tion was paid to the fungus than to its effects on the apple. 

 It is suggested that, since it was discovered in America nearly a 

 century ago, the pathogene was carried across the ocean from 

 the United States to England. It has frequently been observed, 

 for many years, in English markets on American-grown apples. 

 On its discovery in the latter country, in 1910, its history with 

 particular reference to its origin aroused great curiosity. Eng- 

 lish growers of fruit had not forgotten their experience with in- 



