336 



PL Americana, E. & E. 



Pleospora hyalospora, E. & E. Proc. Acad. Nat. Sci. Phil. July, 1890, p. 238, (not 

 Speg.) 



Perithecia scattered, depressed-hemispherical, 75-90 /i, of coarse, 

 cellular structure, at first sunk in the parenchyma of the leaf, finally 

 more or less erumpent-superficial, with a papilliform ostiolum. Asci 

 oblong, 75-85 x 35-40 //, 8-spored. Sporidia oblong or slightly ovate- 

 oblong, 3-6-septate (mostly 5-septate), with one or more longitudinal 

 septa more or less distinct, nearly hyaline, ends obtusely pointed or 

 rounded, slightly constricted at the septa, especially at the middle one. 

 25-40 (mostly 25-30) x 12-15 u. Differs from P. Pisi (Sow.) in its 

 obovate asci, nearly hyaline sporidia, and more delicate, smaller peri- 

 thecia. 



On leaves of Lathyrus sativus and Pisum sativum, Starkville, 

 Miss. (Tracy), and on leaves of Trifolium, Canada (Dearness). 



PL compressa, Hark. Bull. Cal. Acad. Sci. No. I (1884), p. 45. 



Perithecia scattered, covered by the blackened cuticle, concave, 

 surrounded by radiating, brown hyphse. Asci clavate, short-stipitate, 

 8-spored, paraphysate, 80-90 x 15-18 [i. Sporidia biseriate, unequally 

 elliptical, transversely 3-septate, brown, with a longitudinal septum 

 across the two central cells, at first surrounded by a gelatinous coat, 

 20-27 x 10-19 /i. 



On dead stems of Polygonum amorphum. Blue Canon, Cal. 

 (Harkness). Very near PI. permunda, Cke. 



PL vitrispora, Cke. & Hark. Grev. IX, p. 86. 



Exsicc. EH. & Evrht. N. A. F. 2d Ser. 1582. 



Perithecia scattered, buried in the wood, the surface of which is 

 raised and blackened over them, about J mm. diam., globose, papillate, 

 and finally perforated, black. Asci cylindrical, about 112x12 //, with 

 abundant paraphyses. Sporidia uniseriate, elongated-elliptical, hya- 

 line, the contents divided in a muriform manner (merenchymatic), 22- 

 24x12 a( 32x1 2> Cke.) 



On dead branches of Lonicera, California. 



PL denotata, (C. & E.) 



Spharia denotata, C. & E. Grev. VI, p. 16, Pi. 96, fig'. 20. 

 Pleospora denotata, Sacc. Syll. 3740 and Cke. Syn. 5027. 

 Exsicc. EH. N. A.F. 778- 



Perithecia mostly seated on pallid spots, globose, large, promi- 



