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 sooty-blotch and 
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- 
Fic. 29. — Fly-speck. 
