224 



ASCOMYCETES. 



rupture of the epidermis. Numerous leaves may be diseased 

 and each carry many cushions, yet Vuillemin, who described 

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

 serious degree. 



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

 black 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 to that of M. fimlriata. 



Fio. lOS. — Mamiana fimbi'iata on Ca'rpinus Beiulus. Leaf of Hombeani seen 

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

 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. No paraphyses are present. 



Valsa oxystoma Eehm.^ This causes disease and death of 

 branches of Alnus viridis in the Alps. The symptoms are 

 withering and drying up of single branches on an otherwise 

 green bush. This disease causes severe loss in the Tyrol, 



1 Titres et travaux scientifiquen, 1890. 



^v. Tubeuf. "Zwei Feinde d. A\^eneT\e," Forstlich-naturimss. ZeitschriJ't, 1892. 



