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Journal of Agricultural Research 
Vol. I, No. 4 
conidia. The latter are borne singly, rarely in clusters, and are largely 
straight, with rounded ends. 
The Cercosporas, on the other hand, are mostly parasitic, and form 
leaf spots. The sporophores are developed in thick bundles, either 
through the stomata and from mycelium within the leaf tissues which 
often takes the form of a stroma beneath the stomatal opening or by 
sporophores breaking through the epidermis irregularly. The conidia 
are longish-cylindrical or spindle-shaped, occasionally somewhat club- 
shaped, straight or bent, and often with a long drawn-out point. 
As observed in the humid sections, the typical forms of this fungus 
had the densely clustered sporophores which, occurring mostly on the 
upper leaf surface, have arisen from a stroma breaking through the 
epidermis rather than through the stomatal openings. (Fig. 3.) The 
mycelium is largely within the leaf tissue and is intercellular, but is also 
found creeping over the leaf surface and giving rise here and there to 
single conidiophores. In the semiarid sections the latter type of spore 
formation appears to be the more frequent. The conidia are long, usu¬ 
ally somewhat club-shaped, and with the apical end the more pointed. 
It will be seen that the fungus possesses some characters of both 
genera. However, since under conditions favorable to fungus growth the 
Cercospora characters greatly predominate, it has seemed best to place 
it in this genus. Of course parasitism or nonparasitism should scarcely 
be given a generic value, but this point at least adds further weight to 
the present decision. Furthermore, since a Cercospora diffusa has been 
previously described by Ellis and Everhart * 1 as occurring upon leaves of 
Physalis lanceolata , it becomes necessary to change also the specific name 
of this pecan fungus. The emended description of the fungus is given 
below. 
Cercospora fusca, emend, sp. 
Syn. Clasierosporium diffusum Heald and Wolf. 
Leaf spots up to 10 or 15 mm. in diameter, at first somewhat angular and bounded 
by the veins, becoming roundish to irregular and with more indefinite margin, dark 
reddish brown on both leaf surfaces. 
1 Ellis, J. B., and Everhart, B. M. Additions to Ramularia and Cercospora. Jour, of My col v 4 no 
1, P. 3. 1888. * 
