296 PovaH: A CRITICAL STUDY OF 
‘This species was obtained twice, from decayed leaf and as a 
contamination in a culture. Both of these the writer received 
from Mr. E. Levin. Nos. 49 and 50. It belongs to the M. race- 
mosus group of mucors but can readily be distinguished from the 
above-mentioned species by the color of the turf, which is nearest 
to that of M. plumbeus, although it is slightly lighter. The branch- 
ing in M. sphaerosporus is much more profuse than in M. race- 
mosus; and while the spores are very similar in the two species, 
the chlamydospores are different. In M. sphaerosporus they are 
globular and have a central oil globule. 
This species forms a hair brown (Ridgway) turf, 1-2 cm. tall 
on rice, without any yellowish coloration near surface of sub- 
stratum; on grapefruit a 7-8 mm. tall, gray turf is produced. 
Dextrose is fermented but tyrosin is not oxidized by this species. 
g. Mucor aromaticus sp. nov. 
Forming on bread a loose, yellow ochre to ochraceous orange 
(Ridgway) turf, 2-3 cm. tall; sporangiophores 20-50 win diameter, 
typically unbranched or with one to three lateral branches always 
terminating in a sporangium; sporangia globose, 100-160 wu in 
diameter, encrusted with small crystals, more or less transparent, 
showing the spores within; sporangium wall deliquescent, without 
or with basal membrane; columella free, subglobose to oval, ap- 
proaching pyriform, 51-121 X 43-105 uw, with or without proto- 
plasmic contents, hyaline; spores uniform elliptical, 18-20 K 10 » 
(extremes 15-35 X 7-14 »), a few oval, also approaching spherical; 
culture strongly aromatic, with odor somewhat like camphor and 
celluloid; zygospores not found (species presumably heterothallic). 
[PLATE 17, FIGS. 7—-I1.] 
This species is characterized by its ochraceous color and its 
odor. Its origin was dung (squirrel?), and the writer is indebted 
to Professor J. B. Pollock, who collected it. No. 24. 
Mucor aromaticus varies with the substratum as may be seen 
from the following data. On potato agar it grows 32 mm. tall; 
on bean agar, 20 mm.; on apple agar, 11 mm.; on rolled oats, 30 
mm.; on cornmeal, 20 mm.; on starch paste, 20 mm.; and on rice, 
20-30 mm. (often coloring the whole substratum yellow). It 
ferments dextrose (slight amount of alcohol found on second dis- 
tillation), but does not oxidize tyrosin. Cultures on the following 
substrata were strongly aromatic: rolled oats, cornmeal, beef 
