FAIRMAN : ASCOMYCETES FROM NEW MEXICO 



249 



Pyrenophora com ata (Awd. & Niessl) Sacc. 



On old stems of Petalostemum oligophyllum (Torr.) Rydb. 

 (14719 p.p.)- Associated with Hcndersonia Petalostemonis. 



Pyrenophora Leucelenes sp. nov. 



Perithecia black, minute, 100-150 /x in diam., scattered, im- 

 mersed, becoming erumpent-superficial, globose, crowned with a 

 few short, stout setae, brown at base, hyaline at tips, straight and 

 rigid, 20-70 fx long and 3-4 fi broad ; asci obovate, rounded at apex, 

 short-stipitate, 8-spored, 80-85 X 30-33 ,u ; spores irregularly 

 tristichous or conglobate, 6-7-septate, constricted at the middle 

 septum, upper half of the spore more obtuse, the obtuse portion 

 with bulging episporic wall from the middle septum up to the 

 second septum from the middle, cells divided by 1-3 longitudinal 

 septa, yellow at first, becoming dark-brown and finally opaque, 

 30 X 13-33 



Distinguished by minute perithecia, short, broad asci and bulg- 

 ing-walled spores. 



On stems and leaves of Leucelene arcnosa Heller (13572). 

 Accompanied by several deuteromycetes which may be stages of 

 the development of the Pyrenophora. Inasmuch as these fungi 

 imperfecti are so minute, and the leaves and stems of the host 

 also, it was not practicable to separate them and all are included 

 in one packet. It seems best, therefore, to describe them in this 

 connection. 



1. Hendersonia Leucelenes sp. nov. 



Pycnidia scattered, globose-depressed, black, about 250 /x in 

 diam. ; spores oblong, straight or curved, varying from obtuse to 

 subacute at the ends, 3-septate, not markedly constricted, hyaline 

 and nucleolate at first, becoming brown, 10—14 X 4-6 fi ; basidia 

 inconspicuous. 



2. Microdiplcdia Leucelenes sp. nov. 



Pycnidia immersed or suberumpent, globose or globose-de- 

 pressed, brown or blackish, 100 p in diam.; spores numerous, ex- 

 uded in a mucous mass, oblong or ellipsoid, uniseptate, not con- 

 stricted, ends rounded, 7-9 X 3-4/*, brown, with basidia concealed 

 by mucus. 



