480 FUNGI IMPERFECTI. 



pustules bearing the pycnidia of this Mclasmia. The cells of 

 the cortex dried up, and the rind became detached from the wood 

 in the following year. The leaves were never found attacked. 

 (The species is not a Rhytisma ; nor does any species of Rhytisma 

 produce similar hypertrophy of its host.) 



M. acerina, M. punctata, and M. salicina are now recognized only as 

 pycnidia of the species of Rhytisma bearing these same specific names. 



Leptostroma. 



Pycuidia oblong, black, and flattened. Conidia ovoid or 

 oblong, unicellular, and whitish. 



Leptostroma punctiforme Wallr. Found on the leaves of 

 Salix, Rosa, Buxus, Euphorbia, etc. 



L. caricinum Fr. frequents leaves of Carex and Eriophorum 

 in Europe and North America. 



The parasitism of other species is uncertain. 



Labrella and Discosia are genera whose species have not as yet pro- 

 duced diseases of any serious economic importance. 



PHRAGMOSPORAE. 

 Entomosporium. 



Entomosporium maculatum (D.C.) Lev. 1 This fungus, under 

 the name of leaf-blight of pear and quince, is the cause of 

 considerable loss in the cultivation of these crops. Defoliation 

 takes place early in the season and young seedlings are forced 

 to form a new set of leaves, whereby their reserves of food are 

 exhausted. If this be repeated several times the plants become 

 exhausted and are killed off in winter. Stocks already budded 

 seem to remain immune if not already diseased. The leaves 

 are first attacked, but later the succulent growing apex of the 

 twigs may also succumb. The parasite hibernates on the bark 

 in small depressions containing the pycnidia ; thence it spreads 

 in early spring, so that pustules appear on the young leaves 

 before they are fully developed. 



Spraying with Bordeaux mixture, or solution of copper acetate 



1 Galloway and Southworth (Report fur 1888 of Section of Verjc.tal>l<>. Pathofoijy, 

 Dept. of Agriculture, U.S. America) give a historical account of the fungus 

 and a bibliography. (Edit.) 



