39 



SPHAEROTHECA MORS-UVAE, (Scliw.) Berk, and 'Curtis. Goose- 

 berry and currant blight, on leaves of cultivated gooseberry, 

 and wild black currant (Ribes floridum). Not common 

 enough to be injurious. June. 



MICROSPHAERA ALNI, (DC- ) Winter. Lilac blight. On leaves 

 of lilac (Syringa vulgar is}. Bare. Causing but little dam- 

 age. June July. 



ERYSIPHE COMMUNIS, (Wallr. ) Fr. Pea blight, Common on 

 leaves and stems of garden peas. This fungus was not so 

 destructive this season as it has been in previous ones. It 

 often becomes a serious pest. June July. 



PYRENOMYCETES. THE BLACK FUNGI. 



SPHAERIA ULMAE, Schw. On leaves of White Elm (Ulnnis 

 americana). It forms irregular blackish spots on the leaves 

 but appears too late in the season to do much damage. 



PHYLLACHORA GRAMINIS, (Pers.) Fkl. Leaf spot. Forming 

 elongated black spots on the leaves of Muhlenberg's grass 

 (Muhlenbergia mexicana) and rice-cut-grass (Leersia vir- 

 ginica). Although the fungus is very plentiful it seldom 

 does much injury as it generally appears late in the season 

 when the leaves are dead or dying from frost. 



PLOWRIGHTIA MORBOSA, (Schw.) Sacc. Black-knot. On limbs 

 of wild plum (Prunus americana ) and choke cherry (Prunus 

 virginiana), causing great black swellings, deforming and 

 finally killing the limbs. Very common and injurious. In 

 many states this fungus has become so bad on cultivated 

 plums as to completely ruin large orchards. The only reme- 

 dy is to cut off and burn all deseased parts year after year, 

 taking care that no affected parts are allowed to remain over 

 from one season to another. 



DISCOMYCETES. THE CUP-FUNGI. 



KHYTISMA ACERINUM, ( Pers. ) Fr. Black leaf spot of maple. On 

 living leaves of soft or silver maple (Acer saccharinum), 

 forming large, irregular, thickened, black, areas. Thus far this 



