NEW OR PECULIAR ZYGOMYCETES. 3: BLAKESLEA, 



DISSOPHORA, AND HAPLOSPORANGIUM, 



NOVA GENERA 1 



Roland Thaxter 



(with plates xxvi-xxix) 



Blakeslea, nov. gen. 



Mycelium copious, cottony; hyphae very irregular in diameter, 

 the copious branches often rhizoidal and contorted and producing 

 numerous intercalary chlamydospores. Sporangia of two types 

 with numerous intergrading variations: larger solitary sporangia 



like those of Choanephora, with columella and dark appendiculate 

 sporangiospores ; and sporangiola without columella, containing 

 few dark appendiculate spores and covering the surface of large 

 spherical sporangioliferous heads to which they are attached by a 

 vesicular basal piece; the heads solitary on the ends of erect fertile 

 hyphae or produced in clusters from the numerous ultimate branch- 

 lets which may result from the successive branching of the latter. 



Blakeslea trispora, nov. sp. — Plates XXVI and XXVII. 



Mycelium colorless to bright orange. Fertile hyphae stout, 



terminally 



Spo- 



rangia spherical, nodding or circinate, very variable; the larger 

 spherical with a rough granular wall, the columella from hemi- 

 spherical to more elongate; the smaller more conspicuously and 

 coarsely roughened, as is often the distal end or more rarely the 

 whole of the sporangiophore, with spores often distinctly larger 

 and the columella frequently obsolete. Sporangioliferous heads 



solitary 



or typically in 



more 



terminating branchlets of the subdichotomously branched extremity 

 of the fertile hypha, the branches and branchlets of which are 



1 Contributions from the Crvptogamic Laboratories of Harvard University, 

 LXXV. 



353! 



[Botanical Gazette, vol. 58 



