446 Bulletin 315 



Absidia spinosa Lendner, Bui. Herb. Boissier ser. 2, 5: — . 1905; Les 



Mucorinees de la Suisse, 132-134. fig. 46. 1908. 



Syn. Absidia cylindrospora Hagem, Untersuch. li. Norw. Mucorineen i: 45-46. 

 fig. 21. 1908; reprint from Vid.-Selsk. Skr. I, Math.-Naturv. Klasse No. 

 7. 1907- 



Culture forming very dense, grayish, cotton -like aerial mycelium which 

 attains a height of 2.5 cm.; stolons slightly incurved ; curves carrying 

 sporangiophores in fascicles of 2 to 3; sporangia pyriform, measuring 34/x 

 long without the apophysis and 28/i thick; columella 20 ix thick, vase-like 

 in form, terminated by a blunt or round point, attaining one third of the 

 length of the columella. A septum situated 25/i below the apophysis 

 separates the sporangia from sporangiophores; spores hyaline, oval or 

 short cylindrical, 2 by 4-5/x. 



Zygospores globose or dulifonn, verrucose, formed by the fusion of two 

 unequal gametes supported by a bifurcated filament. The most vigorous ■ 

 suspensor alone produces prolongations or circinate appendages. 



Hab. Isolated from garden soil, Geneva, Lendner; from humous soil 

 near Christiania, Norway, Hagem. 



Rhizopus 



Rhizopus nigricans Ehrenberg, Mucor Stolonifer in Sylv. Myc. Berol., 



25. 1818; Rhizopus nigricans in Nova Acta Acad. Leop. 11: 198. 1820. 



Stolons far-spreading, even growing onto and spreading 



over the culture glass, covering the substratum and its 



neighborhood with thick cobwebby growths 1-3 cm. long 



and occasionally still longer, simple or sparsely branched, 



occasionally fork-like internodes, with smooth, at first 



hyaline then finally brown, membrane, contents colorless; 



Fig. loi. —Rhi- rhizoids more or less richly branched, at first with color- 



zoptis nigri- jess, later with brown or black-brown, smooth, thick 



CCDIS Elf I VOX 



A, columella membrane, as thick as i6^i at base and sn at tip, finally 



•with adhering uniseptate; sporangiophores seldom single, mostly in 



apophysis, X clusters of 3-5 occasionally up to 10, unbranched, 0.5-4 



60; B, colli- rnm. high, 24-42^1 thick, with smooth, finally brown or 



coming pileate, black -brown, membrane, contents colorless, with apophysis 



x6o;C, spores, of sporangium more or less hemispherical, large, 100-350)1* 



broad, at first snow-white then becoming at maturity black, 



erect; columella with broad base, very large, broadly half globose, highly 



arched, with apophysis 70/i broad by 90^ high to 250/1 broad by 320/i 



high, with brown smooth membrane, often covered with spores after 



opening of sporangia, often becoming pileate; spores irregularly globose 



or broad oval, mostly with one or two blunt corners, variable in size 



