341 



to have been somehow interchanged and confused. Those here given 

 have been made very carefully and may be relied on. 



Every one who has had much to do with the microscopical exam- 

 ination of Ascomycetes will recognize the fact (noted by Dr. Winter 

 in Die Pilze, p. 454) that in Leptosphceria, Pleospora and many other 

 Ascomycetes, the length of the asci, in the same perithecium, is often 

 very variable, depending on whether the ascus has become elongated 

 by the absorbing of water, in the course of the microscopical exam- 

 ination. 



PI. planispora, Ell. Bull. Torr. Bot. Club, X, p. 53. 



Clathrospora planispora, Berl. Mon. p. 200, tab. IX, fig. 5.* 

 Exsicc. EH. & Evrht. N. A. F. 1584. 



Perithecia gregarious, covered by the scarcely discolored epider- 

 mis, 250-330 [i diam., collapsing when dry, of coarse, cellular structure. 

 Asci 114-120x25-28 /*, p. sp. 80 /j. long, with abundant paraphyses. 

 Sporidia biseriate, oblong-elliptical, 5-septate, with a longitudinal sep- 

 tum running through all but the terminal cells, 30-40 x 1 5-20 /i, and 

 7-1 1 fi thick. 



On dead culms and sheaths of some grass (Elymus)? Pleasant 

 Valley, Utah (S. J. Harkness). The perithecia are mostly on the 

 sheaths which are clouded or mottled with a darker color in those 

 parts occupied by the fungus. The sporidia are larger than in PL 

 aurea, and 5-septate ; the perithecia also are larger and mostly lack 

 the fringe of mycelium around the base. 



PI. oligomers Sacc. & Speg. Mich. I, p. 408. F. Ital. tab. 331. 



Perithecia loosely gregarious, innate-erumpent, becoming nearly 

 superficial, depressed-globose, J-J mm. diam., black and somewhat 

 shining, obtusely papillate, finally umbilicate-collapsed. Asci cylin- 

 drical, rounded at the apex, very short-stipitate, 90-100x15-16 //, 

 paraphysate, 8-spored. Sporidia obliquely uniseriate, oblong-ovoid, 

 20-22x9-11 jut, 3-septate, slightly constricted at the septa, with a 

 longitudinal septum across two or more cells, yellow, becoming brown. 



On Silene Gallica, California (Harkness). 



PI. penniinda, Cke. G-rev. V, p. 111. 



Clathrospora permunda, in Berl. Mon. p. 195. 

 Exsicc. EH. N. A. F. 8g6. 



Perithecia scattered, at first covered by the epidermis, at length 

 erumpent and collapsing above, 200-250 p. diam., fringed below with 

 a mycelium of dark brown, branching, septate threads spreading out 



*The genus Clathrospora, characterized by its reticulate sporidia, is with difficulty dis- 

 tinguished from Pleospora, and we have included all species referred to that genus in Pleospora. 



