298 PovAH: A CRITICAL STUDY OF 
cylindrical to pyriform, 110-160 X 70-113 u, brownish, sometimes 
with orange contents; spores narrowly elliptical in larger sporangia, 
13-16 X 5-6 yu, broadly elliptical in smaller sporangia, 9-12 * 7-8u, 
grayish; chlamydospores rarely in sporangiophores; zygospores not 
found (presumably heterothallic). [PLATE 19, FIGS. I-5.] 
This species is characterized by its varied habit of branching; 
its small, lateral, often deciduous sporangia, recalling Mucor lam- 
prosporus; its cylindrical to pyriform columella; and its variable 
spores, narrowly elliptical and broadly elliptical in the larger and 
smaller sporangia respectively. It is related to Mucor griseosporus, 
from which it differs in its slightly lighter colored and shorter turf; 
more slender and more profusely branched sporangiophores; 
cylindrical to pyriform columella; and its variable (broadly to 
narrowly elliptical), larger, non-agglutinate spores. A. single 
collection was obtained of this characteristic species from rabbit 
dung. No.73. Ellis & Everhart’s North American Fungi 972 is 
certainly not Mucor Mucedo (sporangia and spores too large), and 
probably ought to be referred to M. coprophilus. 
This species forms a 30 mm. tall, Saccardo’s olive (Ridgway) 
turf on rice and a 25 mm. tall, brownish gray turf on grapefruit. 
It produces no color on rice but oxidizes tyrosin and ferments 
dextrose to a slight extent. 
12. Mucor varians sp. nov. 
Forming on bread a dense, ivory yellow to olive buff (Ridgway) 
turf, I-3.5 cm. tall; sporangiophores 8-20 in diameter, either little 
globose, smooth, 60-80 in diameter (extremes 43-116 yp), at 
first yellowish or pale orange, becoming very dark gray, tinged 
green, at maturity; sporangium wall deliquescent, leaving a ba 
membrane; columella free or slightly adnate, very variable in 
shape, subglobose, hemispherical, flattened hemispherical, oval, 
cylindrical, elliptical, pyriform, panduriform, cylindro-conical, 
subconical and conical, large columellae hemispherical to conical, 
small columellae cylindrical to pyriform and panduriform, 25-50 
X 20-45 » (extremes 18-70 X 12-59 4), membrane tinged gray, 
with or without orange contents; spores not uniform, oval to sub- 
elliptical (few spherical), 4-6 X 3-4. (extremes 4-14 X 3-8 #), 
4-8 u in diameter, bizarre spores not rare, reniform, cruciform, 
