154 ASCOMYCETES. 



III. Species whicli produce (1) pustule-like outgrowths, (2) 

 leaf-spot, or (3) smooth coatings of asci. 



E. imrcus (Pers.) on Populus nigra (incl. pyramidcdis) 



and P. monilifcra. 

 E. ]><>li/*i>nras (Sor.) on Acer tartarienm and A. Pseudo- 



platanus. 

 E. ImUntns (Berk, et Br.) on Pyrus communis and Cydonia 



juponica. 

 E. carneus (Johan.) on Betula nana, B. odorata, and B. 



intermedia. 

 E. cocrulcscens (Desm. et Mont.) on Quercus putiescens, Q. 



sessiliflora, Q. Cerris, Q. laurifolir/, (J. r/ibra, Q. tinctoria, 



Q. aquatica. 



E. tiiidclteckii (Johan.) on Alnus glutinosa. 

 E. id mi (Fuck.) on Ulmus campestris, U. montana, and U. 



americana (spots and blisters). 

 E. virginicus (Sey. et Sad.) on Ostrya virginica. 

 E. <itt$fj'nlis (Atk.) on Carpinus americanus. 

 E. Jilicinus (Rostr.) on Aspidium spinulosum. 

 E. potentillae (Farl.) on Potentilla gedidcs, P. canadensis, P. 



sylvestri*. 



E. ijithayinis (Eostr.) on Agrostcmma Grithago. 

 E. lutescens (Eostr.) on Polysticlmm TJielypteris. 

 E. umbelliferarum (Eostr.) on Heradcum Spliondylium, P<'n- 



<'<'<f</num palmtrc and P. Oreosclinum. 



E. <>xti'//'ie (Mass.) on Ostrya carpinifolia (brown spots). 

 E. In in] <ie, (Tuck.) on Betula nTi'in-osa, B. pvl>cwns, B. 



turkesta/nica (whitish spots). 



E. jlfic-u* (Farl.) on Betula populifolia, B. />i>//racca. 

 E. "cericolus (Mass.) on Acer m////^.s//r and A. Pscudo- 



platanus. 

 E. fasciculatus (Lag. et Sad.) on Nephrodium (whitish spots). 



The following are some of the more important species of 

 Exoasceae : 



Exoascus pruni Fuck. (Pocket-plums). This attacks the 

 ovaries of Prunus domestica (plum), P. Padus (bird cherry), and 

 P. virginiana, causing the mesocarp to grow rapidly, whereby 

 the fruits increase in size and become much changed in form, 



