83 



Peronospora Plantaginis n. sp. 



Mycelium parasitic in well-defined yellow areas of the leaf, 

 occupying the entire width and a length of I-3 cm.; conidiophores 

 usually solitary, long exserted, irregularly 5-6 times dichotomous ; 

 ultimate ramulae short, unequal, recurved, 4-1 2// long; conidia 

 narrowly oval or lemon-shaped, pointed at each end, dark, almost 

 black by reflected light, brownish violet by transmitted light, 40- 

 44x16-18^. Oospore unknown. 



On leaves of Plantago aristata, Auburn, Alabama, May, 1896. 



F. S. Earle. 



Peronospora Sevmourii Burrill n. sp. 



Sparse, forming white patches or lines on leaves and stems; 

 oospores on floral organs. Mycelium large, distorted, haustoria 

 knob-like; conidiophores slender, seven or eight times dichoto- 

 mous, branches flexuous, spreading, tips short or of moderate 

 length, subulate; conidia subglobose to elliptical, variable, i2-i8/jt 

 by 14-27//, brownish; oogonia with firm, rather thick brownish 

 walls, reaching 'jott in diameter; oospores dark brown, opaque, 

 thick-walled, rough, 27-45 fi. 



On Hoiistonia sp. Union and Jackson counties, Illinois, April 

 11-28,1882. (A.B.Seymour.) 



The above description was furnished me by Professor T. J. 

 Burrill. Having found what appeared to be an undescribed 

 species of Peronospora on Hoiistonia patens , in Auburn, Alabama, 

 I learned by accident that a species had been found on the same 

 host many years ago and that its description written at the time 

 by Mr. Seymour had laid in manuscript until now. The Alabama 

 specimens appear to be the same species, but no oospores were 

 found. In the Alabama specimens the conidiophores were about 

 400 ;u long, with a diameter of about 6//; the branching was alter- 

 nate, the main branches being 70-90// long and the ultimate 

 branches or sterigmata6-io// ; the conidia were more often ovate, 

 21 by 11-14/^. 



Polyporus decurrens n. sp. 



Mesopous; terrestrial ; pileus nearly circular, 5 cm. in diameter, 

 plane or slightly depressed at the centre, brown or bay-colored, 

 covered with a thin crust which is glabrous except where it is 

 raised at certain points to simulate, when dried, an imbricated sur- 

 face ; pores nearly white, forming a layer about 2 mm. deep, de- 

 current on the stem and vanishing in faint reticulations just above 



