319 



form, uniseptate, hyaline sporidia 10-12x3-4 /u, slightly constricted 

 at the septum. 



On dead stems of Ambrosia trijida, Louisiana (Langlois). 



D. subexserta, C. & E. 



Sphceria subexserta, C. & E. Grev. VII, p. 42. 

 Didymella subexserta, Sacc. Syll. 2180, Cke. Syn. Pyr. 4408. 

 Exsicc. EH. N. A. F. 189. 



Perithecia scattered, depressed-globose, J mm. diam., buried in 

 the substance of the stem, with the short-cylindrical, obtuse ostiolum 

 slightly projecting. Asci subclavate, about 60 jul long. Sporidia 

 biseriate, narrow-elliptical, constricted and uniseptate in the middle, 

 each cell 2-nucleate, 10-12 x 3-4 p. 



On dead stems of Lactuca Canadensis, Newfield, N. J., and on 

 Lactuca Floridayia, Louisiana (Langlois). 



D. fruetigena, E. & E. (in Herb.) 



Perithecia scattered or gregarious or 2-3 together, but not con- 

 fluent, 100-150 //. diam., subglobose, prominent, but covered, except 

 the apex and papillifbrm ostiolum, by the thin epidermis ; when grow- 

 ing on the denuded cherry stones, superficial, with the base adnate. 

 Asci oblong-cylindrical, subsessile, 3440x6-7 //, paraphysate. Spo- 

 ridia inordinate, oblong-fusoid, slightly curved, uniseptate and con- 

 stricted, the upper cell abruptly swollen just above the septum, the 

 lower cell narrower and acute, 12-15 x3-3| ju, hyaline. 



On dried up cherries (cult), and on the bare cherry stones lying 

 on the ground, Newfield, N. J. 



D. intercellularis, (B. & C.) 



Sphceria inter celhdaris, B. & C. Grev. IV, p. 153. 

 Didymella intercellularis, Sacc. Syll. 2183, Cke. Syn. 4412. 



" Perithecia contained in the larger or dilated cells, about 50 fi 

 diam., with a few radiating threads. Asci short, thicker at the base. 

 Sporidia shortly cymbiform, uniseptate, 12-13 p. long. 7 ' 



On Typha, Massachusetts. 



D. Nebraska^ (B. & C.) 



Sphceria Nebrask.cz, B. & C. Grev. IV, p. 154. 

 Didymella Nebraskce, Sacc. Syll. 2186, Cke. Syn. 4415. 



"Minute, shortly hysteriiform. Asci oblong, slightly swollen. 

 Sporidia elliptical, biseriate, uniseptate, 12-16 fi long." 

 On leaves of grass, Nebraska. 



