FUNGI. 23 



becoming exposed by the shredding away of the weathered 

 tissues of the host, black, small, 200/4 or less, collapsing to 

 saucer-shape, of soft loose-celled panachyma, the cells 

 about lO/^ in diameter, ostioles inconspicuous; asci oval, 

 nearly sessile, about 80x18/4; paraphyses scanty, filiform, 

 slender, continuous; ascospores subdistichous, ovate, ends 

 rounded, brown, 5-7-septate, each cell usually once verti- 

 cal!} 7 divided, slightly constricted at middle septum, medial 

 cells usually much shorter than the end cells, covered at 

 least when young with a hyaline mucous coating 1-4/4 

 thick, 20-30x12/4. 



On dead steins of Senecio, Hermosa, 28 March. Much 

 like forms that have been referred to P. vulgaris, Niessl. It 

 also resembles what is described above as P. compositarum, 

 but differs in the softer large-celled wall of the perithecium, 

 and in the septation and mucous coating of the spores. 



PYRENOPHORA CASTILLEI^E, n. sp. Perithecia scattered, 

 black, buried, becoming exposed by the shredding of the 

 epidermis, 150-200/4, collapsing, covered throughout with 

 crisped, fuscous hairs, 40-100x4/4, these at length deciduous 

 above but remaining as a vestiture below, ostiole perforate, 

 scarcely papillate; asci, oval to ovate, about 80x30/4; para- 

 physes filiform, exceeding the asci; ascospores distichous or 

 inordinate, oval, 5-7-septate, each cell 2-3 times vertically 

 divided, when young yellow and constricted uniseptate, at 

 maturity dark-brown and scarcely at all constricted, 

 25-30xlO-12/x. 



On dead stems of Castilleia, Hermosa, April 5. Resembles 

 P. Eriogoni, following, but differs in the smaller collapsing 

 perithecia and the shorter partially deciduous vestiture, 

 The asci, too, are shorter and the spores are not constricted 

 at maturity. 



PYRENOPHORA CLEMATITIS, n. sp Perithecia black, buried 



