526 



** Sporidia becoming brown (Melanconiella). 

 M. acrocystis, (Pk.) 



Valsa acrocystis, Pk. 33d Rep. p. 34, pi. 2, figs. 19-22. 

 Melanconis biansata, E. & E). Bull. Torr. Bot. Club, X, p. 118. 

 Melanconiella acrocystis^ Sacc. Syll. 662S. 



Perithecia circiriate, 6-12 'together on the surface of the inner 

 bark, subglbbose, J-j mm. diam., enveloped in and covered above by 

 a yellowish-gray, interwoven, felt-like layer; often collapsing, their 

 short, round or subquadrate, obtuse, black ostiola erumpent in a 

 brownish disk bursting through the transversely fissured or subradi- 

 ately-cleft epidermis, which is slightly raised. Asci 190-200 x 25-30 //, 

 stipitate, 8-spored. Sporidia oblong-elliptical, uniseptate, soon becom- 

 ing brown and with a short, hyaline, broad, sub truncate appendage at 

 each end, 35-50 x 15-19 p (without the appendages). 



On dead limbs of birch, Plainfield, N. J. (Meschutt), on Betula 

 lenta, Greenbush, N. Y. (Peck). 



The felt-like covering of the perithecia was at first overlooked, 

 but in both the New Jersey and New York specc. this forms an im- 

 portant character. Valsa acrocystis, Pk., and Melanconis biansata. 

 E. & E v were published at about the same. time. 



M. Meschiittii, E. & E. Bull. Torr. Bot. Club, X, p. 117. 



Diatrype nigrospora, Pk. 33d Rep. p. 35. 

 Melanconiella Meschiittii, Sacc. Syll. 6629. 



Perithecia 10-20, subglobose, \-\ mm. diam. (mostly less than $), 

 seated on the surface of the inner bark, in a thin, dark-colored, orbicu- 

 lar stroma 1J-2 mm. diam. Ostiola rising together in a laterally 

 compressed tuft, united in a dirty-brown or grayish disk erumpent 

 through short, transverse cracks in the epidermis, their tips subcorneal 

 and, in well developed specc, distinctly quadrisulcate. Asci p. sp. 

 about 75x12-15 /*, subsessile, obscurely paraphysate. Sporidia 

 biseriate, oblong-elliptical, very slightly curved, uniseptate and con- 

 stricted, subhyaline at first with a faint, horn-shaped, hyaline append- 

 age at each end, but these are soon absorbed and the sporidia become 

 brown T 14-16 x 6-S> 



On dead limbs of birch, Plainfield, N. J. (Meschutt). 



Gelatinosporium betulinum, Pk., occurs on the same branches. 

 Where the epidermis is thinner, the appearance of the stroma is dif- 

 ferent, it being more prominent with the epidermis sublaciniately cleft 

 around the erumpent disk. The perithecia sometimes collapse so that 

 on stripping off the epidermis, their position is indicated by little 

 circular concavities around the margin of the stroma. Differs from 



