MELANCONIACEAE 427 



MELANCONIACEAE 



Perithecia and asci absent ; conidia produced on a 

 more or less developed cushion or stroma formed beneath 

 the surface of the matrix, and becoming erumpent. 



Probably forms of higher species. 



Gloeosporium, Desm. Sporodochium formed below 

 the epidermis of the host, discoid or pulvinate, at length 

 often erumpent, pallid or brown ; conidia ovate-oblong, 

 .rarely oblong, hyaline, continuous, often extruded in 

 the form of a sphere or tendril consisting of the conidia 

 held together by mucilage; basidia usually acicular, fas- 

 ciculate. 



Grloeosporium nervisequum, Sacc., Mich., ii. p. 381. 

 Pustules hypophyllous, erumpent, slightly prominent, brown, 

 then black, seated on brown, dry patches of the leaf, most 

 frequently following the larger veins, but sometimes form- 

 ing broad patches; conidiophores slender, 12-15x4-6 p.; 

 conidia oblong-ovate or pear-shaped, hyaline, 12-15 x 5~6/*- 



On living leaves of Platanus orientalis, P. ocddentalis, 

 also other species of Platanus, and said to occur on oak 

 leaves in the United States. 



Distr. Europe, United States. - 



Grloeosporium ribis, Mont, and Desm. in Kicktf Fl. 

 Crypt. Fland., ii. p. 95. Spots minute, rounded, often con- 

 fluent, brown ; pustules epiphyllous, blackish, flattened ; 

 conidia hyaline, oblong, curved, apex obliquely pointed, 

 10-12 X5-6 fj.. 



On living leaves of Ribes nigrurn, R. rubrum, R. aticu- 

 lare, and R. grossulariae. 



Distr. Europe, Asiatic Siberia, Australia, United States. 



