AT FAYETTE, low A. 7 



brown, reticulations obscure; appendages short, delicate, hyaline or slightly colored, 

 interwoven with and overrun by the dense mycelium; ascus broadly elliptic, eight- 

 spored, both ascus and sporidia smaller than in S. pannosa. 



On Rides rotundifolium. 



This parasite may be found early in the season, at about the time 

 the fruit is ripe. 



3. S. Mali, (Duby.) Burrill. 



Amphigenous. Mycelium white, submembraneous, persistent. Peritheci 1 few 

 or numerous, immersed In the mycelium, small 75-S5 u , globose or subpyriform; 

 appendages of two kinds, in part rudimentary, floecose, deeply colored, attached in a 

 broad tuft to the smaller end of the pyriform perithecium, the others strongly de- 

 veloped, rigid, straight or curved, continuous or septate, simple or rarely forked at 

 the extremity, deeply colored at the base, becoming pale outwardly, attached in a 

 loose cluster opposite the rudimentary ones. 2-5 times the diameter of perithecium. 

 Ascus oval to subglobose, sporidia 8. 20-30 // long. 



On Pyrus Mains. 



I found my speennens on the stems of suckers in Mr. Peter Grafs 

 nursery. I do not find this species reported in the Iowa bulletins. 

 Prof. L. H. Pammel says it is found at Ames and is very injurious. 



4. S. HUMUI/I, (DC.) Burrill. 



Mostly hypophyllous. Mycelium inconspicuous or evanescent; perithecia 

 scattered, abundant, mostly rather small, 75-95 //, w^all-textuie firm and compact, 

 though thin, surface smooth, reticulations small, often obscure, usually less than 15 

 it: appendages slender, three or more times as long as the diameter of the perithecium, 

 colored throughout when mature, mostly free from the mycelium; ascus broadly 

 elliptical or suborbicular; sporidia usually 8, large, averaging 20 // long. 



On Agrimonia Kupatoria. 



"The perithecia closely resemble those of .V. pannosa, but it differs 

 in the larger appendages and the much less abundant mycelium." — 

 Burrill. 



5. S. Castagnei, Lev. 



Mycelium abundant and persistent or sometimes inconspicuous, occurring on 

 either or both sides of leaves; perithecia abundant, scattered or somewhat aggre- 

 gated, small, usually about 75 11 , but varying from 60-100 //; texture soft, surface un- 

 even, reticulations very large and irregular, 20-30 u\ appendages long, stout, usually 

 colored throughout, flexuous, somewhat uneven in width, more or less interwoven 

 with the mycelium; ascus rather small, elliptical or suborbicular; sporidia usually 8, 

 small, about 15 11 long. 



On Hi dens fro/idosa, Erigeroh Canadensis and Sonchus oleraceus. 



Erysiphe, (Hedw.)Lev. 



Perithecium containing several asci; appendages simple threads similar to and 

 frequently interwoven with the mycelium. 



1. E. communis, (Wallr.) Fr. 



Amphigeuous. Mycelium abundant, persistent or sometimes evanescent; 

 perithecia variable in size and reticulations; appendages variable in length, often 

 quite long, lying on the mycelium or more or less interwoven with it, usually colored 

 in part or throughout, but occasionally all hyaline; asci 4-8, or more; sporidia 

 mostly 4-8, variable in size. 



On (KnotJiera biennis and Astragalus Canadensis. 



The perithecia were about 85 u on the first named host, and fully 

 100 u on the second. The appendages were shorter on the last, and in 

 both they contained little color. 



2. E. GRAMINIS, I) C. 



Amphiyenous. or often epiphyllous. Mycelium dense, felt-like, persistent. 

 white or eray -ometimes tinted brown. Perithecia immersed in tin mycelium, few 

 and scattered or many and crowded, depressed, large, about 225 //; appendages 1111111- 



