693 



or nearly so, each cell with a single nucleus, 18-25 x 7-9 u. (27-33 x 

 8-10 /z, Sacc. and Karst.) 



Common on bark of various deciduous trees. 



Very variable in the shape of the perithecia, which in the typical 

 form are short and broad, subelliptical, but elongated-oblong forms are 

 not uncommon, though in this respect the European specc. show less 

 variation than the American. We do not find the sporidia as large as 

 stated by Sacc. mostly about 22 x 7 fi. H. betulignum, Schw, is 

 given as a synonym from an examination of specc. in Herb. Schw. 



H. truncatulum, C. & P. Disc, of the U. S. p. 33. 



Gregarious, superficial, elliptical, abruptly rounded at the ends, 

 straight, longitudinally striate, flattened along the apex, 1 x J mm. 

 lips closely connivent. Asci clavate, shortly stipitate. Sporidia 

 biseriate, fusiform, rounded at the ends, triseptate, ultimate cells short- 

 er, hyaline, central cells brown, 35-40 x 10 p.. 



On wood. N. York (Peck). 



This can hardly be more than a large-spored var. of H. pulicare. 



H. angustatum, A. & S. Consp. p. 55. 



H. pulicare, b. angustatum, Fr. S. M. II, p. 580. 

 Hysterium vulgare, De Not. Pir. Istr. p. 18. 

 Hysterium Eucalypti, Phil. & Hark. Grev. XIII, p. 23. 

 Hxsicc. Rehm Asc. 214. Sydow, M. March. 2426. 



Perithecia gregarious or crowded, more or less immersed in the 

 bark or often superficial, mostly elongated or linear, nearly smooth, 

 black, -l| mm. long, lips more or less open. Asci 75-80 x 1 2 1 5 /^. 

 Sporidia subbiseriate, oblong, obtuse, 3-septate, all the cells brown, 

 and usually with a single nucleus, 15-22x 6-7 //(18-27 x6-7 ju Sacc). 



On wood, Vermilion Lake, Minn. (Holway), on bark and wood of 

 dead limbs, Carolina and Pennsylvania (Schw.) 



In Schw. Syn. N. Am. the following varr. are mentioned as found 

 in Pennsylvania: var. lenticulare, Fr., round or elliptical, minute, 

 smooth, only half as large as the normal form; var. Iceve, Pes., ellipti- 

 cal, elongated, swollen, smooth; var. Juglandis, Schw., ovate, black, 

 lips swollen, subdistant, bistriate; frequent on bark of Juglans, Penn- 

 sylvania. This differs from H. pulicare, Pers. in having the sporidia 

 swollen and all the cells uniformly brown, with the perithecia less 

 prominent and mostly smaller and more elongated. Fries & Duby 

 make it a mere var. of H. pulicare. Specimens of Hysterium Eu- 

 calypti, Phil. & Hark, (from Harkness), do not differ in any way 

 from this. 



