265 



Tlie specimens were then gone over most earefull}', and the following 

 classification prepared, including only the species that have come under 

 our observation, although a review of the remaining six species listed by 

 Macbride showed that they would fit into and complete most perfectly the 

 classification which we had worked out. For convenience, the species 

 have been placed in three groups. 



CLASSIFICATION OF THE SPECIES OF STEMONITIS. 



Generic character— the superficial net. 



Basis of species classification— spores; their markings, size and color. 

 Other structural characters important in separation of species— inner 

 and outer net structures of capillitium; height of sporangia, and 

 general color. 



a. Epispore smooth or only slightly warted, with low, scattered 

 warts. Spores small, light colored or colorless. 



1. Stemonitis pallida W'ingate. 



Spores nearly or quite smooth, 4-5//, pale reddish 

 brown; capillitium, inner network dense; outer net 

 meshes small, Q-13 fi; height of sporangia, 4 mm., 

 brownish purple, becoming pallid with age. 



2. Stemonitis axifera (Bull) Macbr. 



Spores with low, scattered warts, 5-6i4,«, pale red- 

 dish brown; capillitium as in S. pallida; height of 

 sporangia 5-10 mm., ferruginous, with purple tinge 

 after spore dispersal. 



3. Stemonitis Smithii Macbr. 



Spores minutely warted. ofi, pale dusky brown; 

 capillitium more open than in S. axifera. outer net 

 meshes 6-15//; height of sporangia. 5-12 mm., bright 

 yellowish brown, rusty, paler after spore dispersal. 



4. Stemonitis ■ — ■ 64 (collection numbei*). 



Spores smooth, or nearly so. 5u, pale dusky brown, 

 not reddish; capillitium. inner network open, outer 

 net with small meshes 10-25//, height of sporangia 

 10 mm., dark purple brown, like S. maxima. 



