FUNGI IMPERFECTI. 463 



I. SPHAEROPSIDEAE. 



Conidia abjointed from conidiophores contained in dark- 

 coloured pycnidia somewhat spherical in form. The various 

 species are provisionally arranged in genera according to the 

 colour of the conidia and the number of cells contained in 

 them. The families here included are the Sphaerioideae, Nec- 

 trioideae, L&ptostromaceae, and Excipulaceae. 



I. FAM. SPHAERIOIDEAE. 



Hyalosporae. 



Phyllosticta. 



Fungi with colourless spores, and producing sharply defined 

 spots on living leaves. They occur on all kinds of woody plants, 

 but as a rule the injury caused is too slight to be called a disease. 



From the long list given by Saccardo (Vols, in., ix., and x.) 

 the following have been selected : 



Phyllosticta persicae Sacc. This produces on leaves of peach 

 brownish-yellow spots, frequently marked by concentric zones. 

 The name " shot-hole fungus " has sometimes been applied to 

 this and other allied forms, because the leaves become more or 

 less perforated by the withered spots falling out. The pycnidia 

 on reaching maturity rupture the lower epidermis of the leaf 

 in a star-like manner. Briosi and Cavara do not regard this 

 parasite as very harmful, because leaves attacked by it remain 

 alive without serious prejudice to their function. 



Ph. pirina Sacc. has been observed injurious to pear-trees at 

 Geisenheim (Germany). 



Ph. pmnicola Sacc. is the cause of spotting of leaves of 

 apple, plum, cherry, and apricot. (U.S. America.)^ 



Ph. cytisi Desm. On leaves of Cytisus Lalurnum in 

 Britain and Europe. 



Ph. acericola Cook et Ellis. On various species of 

 maple {Acer dasycarpum, etc.). It is described by Galloway^ 



^The chief authorities for the occurrence of the "Fungi imperfecti " in 

 Britain and North America are Massee (British Fungus Flora, 1895), Farlow 

 and Seymour [Host-Index for U.S. America, 1891), and Saccardo (Sylloge 

 fungorum). Professor J. W. H. Trail kindly revised the records for Britain. 

 (Edit.) 



2 Galloway, "Report of sect, of Veget. Pathology for 1888." U.S.A. Dept. 

 of Agriculture, Washington. 



