14 



Mycologia 



acervulis nigris, minutis ; conidiis cylindraceis, hyalinis, continuis, 

 rectis v. leniter curvulis, 15-24 X -7$—l v<- 



On leaves of Ulmus crassifolia Nutt. Austin, 307 (type). 



The small-leaved elm is affected by a leaf spot which shows as 

 brown, circular or slightly irregular areas, generally with a gray 

 center and a narrow yellow border. The under surfaces of the 

 spots are more uniformly brown and show minute black specks, 

 the acervuli of the fungus. In a few cases the acervuli may be 

 found on the upper surface. 



Cercospora adusta 



Areis magnis, marginalis, atro-brunneis ; maculis veteribus 

 adustis, juvenibus dilute brunneis, margine flavida late cinctis; 

 conidiophoris amphigenis, caespitosis, brunneis, septatis, 100- 

 150X4-5/*; conidiis dense granulosis, subhyalinis, pluriseptatis, 

 85-160 X 3-4/*- 



On leaves of Ligustrum calif ornicum Hort. Falfurrias, 2471 

 (type) ; Floresville, 2851. 



This species forms dark-brown areas involving large spots fre- 

 quently extending from the tip downward or from the margin in- 

 ward. Rarely are the spots removed from the margin. The 

 older diseased parts become very dark and the newer brown, with 

 a gradual shading out into the chlorotic tissue. 



Cercospora atricincta 



Maculis irregularibus, angulatis, centro griseis, brunneo 

 marginatis, 1-2 mm. diam., interdum 4 mm. diam., late purpureo 

 marginatis ; conidiophoris amphigenis, caespitulis minutis, septatis, 

 45-70 X 3-5-4-5 conidiis dilute brunneis, pluriseptatis, clavatis, 

 100-200 X 4~4-5 h~ 



On leaves of Zinnia sp. San Antonio, 1381, 1660; Victoria, 

 2506 (type). 



This disease, rather common in gardens, is characterized by the 

 presence of irregular, angular, gray spots with a brown border. 

 When the spots are abundant this border is narrow and the spots 

 are small, 1-2 mm. in diameter. When they are few they may be 

 4 mm. in diameter, with a broad marginal zone of purple or dark- 

 brown. 



