32 PLANTS BAKERIAN^E. 



PLATYSTOMUM ACERIS n.sp. (LophidiumSacc.) Perithecia 

 scattered, black, rough, compressed, f-lxj-fmm, ostiolum 

 depressed, elliptical; asci oblong, stipitate, 100-1 20x14-1 6/x; 

 paraphyses numerous filiform; ascospores obliquely mono- 

 stichous, oval, 3-septate, deeply constricted at the middle 

 septum, muriform, dark brown, 17-18x9-10/A. 



Dry decorticated twigs of Acer glabrum, upper La Plata 

 River, 10,000 feet, July 13, n. 1107. 



PLATYSTOMUM ALPINUM n. sp. (Lophidium Sacc.). Peri- 

 thecia widely scattered over considerable areas, becoming 

 subsuperficial, black, rough, hemispherical or slightly oval, 

 fxl mm, ostiolum obscurely papillate, inconspicuous, slightly 

 elongated; asci cylindrical, short-stipitate, 140-160x12-14^; 

 paraphyses numerous, filiform; ascospores obliquely mono- 

 stichous, broadly elliptical or ovate, brown becoming opake, 

 5-septate, sharply constricted at the middle, central cells 

 with long longitudinal septa, 20-22x8-1 0/x. 



Dead barkless wood of Populus tremuloides, Bob Creek, 

 10,500 feet, June 27, n. 170. The asci and spores are much 

 as in Lophidium trifidum E. & E., but the gross characters 

 are very different. 



PLATYSTOMUM AMELANCHIERIS n. sp. Perithecia scattered, 

 deep seated, black, rough below shining above, nearly hemi- 

 spherical, J-lmm, ostiolum inconspicuous, often irregularly 

 elongated; asci cylindrical, stipitate, 14 0-1 50x1 3-1 5/*; as- 

 cospores obliquely monostichous, fuscous, becoming opaque 

 elliptical with usually acute ends, 3-5-septate, muriform, 

 slightly or not constricted, 22-24x7-8/A. 



On decorticated branches of Amelanchier at Mancos, June 

 23, n. 1110. 



PLATYSTOMUM DESERTORUM n. sp. Perithecia scattered, 

 subsuperficial, black, rough, usually hemispherical but some- 



