224 



ASCOMYCETES. 



rupture of the epidermis. Xumerous leaves may be diseased 

 and each carry many cushions, yet Yuillemin, who described 

 the disease, 1 does not believe the host-plant is affected to any 

 serious degree. 



M. (Gnom. ) coryli Uatsch. (Britain and U.S. America). The 

 l)lack stromata are found in withered spots on the leaves of 

 hazel (Corylus) ; as a rule, each stroma carries only one peri- 

 thecium with a long beak similar t<> that of M. Jinil>i-it. 



FIG. 108. Mamiana fimbriata mi Ci'i-jiiiii'/t Biti/lt'*. Leaf of Hornbeam seen 

 on lower surface. Stroma (enlarged), with the long black necks of the perithuda 

 projecting from the ruptured leaf-epidermis, (v. Tubeuf del.) 



Valsa. 



A stroma is generally present, but is of very variable appear- 

 ance ; embedded in it are the perithecia, with only their beak- 

 like mouths projecting. The spores are hyaline or light-brown, 

 unicellular, and generally bent. Xo paraphyses are present. 



Valsa oxystoma Rehm. 2 This causes disease and death of 

 branches of Alnus rirtdis in the Alps. The symptoms are 

 withering and drying up of single branches on an otherwise 

 bush. This disease causes severe loss in the Tyrol, 



green 



ct tramux scientifiques, 1890. 

 2 v. Tubeuf. " Zwci Feimle d. Alpenerle," Forstlich-naturioiss. 



