
576 REport OF THE “Horrourrerisr OF THE 
above the surface of the leaf. In the center of each i is an opening — 
through which the spores escape and within which appear the | ag 6 
"ha : 
7h 
e 
es" 
: 
_ a=, So 

Fig. 13. Enlarged view of a portion of one of the leaf spots in Figure 12. 
outlines of some of the spores that fill the cavity. The spores, iso- é 
lated and still more magnified, are shown in Vig. i4.* sd ep 

Fig. 14. Spores of the Septoria. SRL : i 
A study of this fungus last season disclosed the inportant fact ie ie 
that the pycnidia may occur on any aerial part of the plant, includ- 
ing the seeds (seed coats), and the pedicels on which they are \\ 4 
porne. Fig. 15, somewhat enlarged from nature, illustrates the way ae 
in which the pycnidia cover the stems and seeds. To the aie 6 ieee 
eye they appear like black specks. | 
While the development of the disease from diseaked seed has 
not been definitely observed, it is certainly true that the disease } se 
appears in the seed bed, and it is reasonable to suspect ‘7 
that the introduction and rapid distribution of the disease in 
this country is due to the importation of infected seed. The - 
more we study plant diseases the more thoroughly are we impressed a * 
with the importance of perfectly sound seed for all farm and gar- | . 
den Pee Various diseases of beans, corn, oe potatoes and~ . 








Bulletin Q of . J Bape. Station, 1892. 
