e° 
1921] SPENCER—BRAZIL NUTS 285 
The filaments are never entirely straight nor yet very crooked, and 
chains of spores are usually contained in the free ends (fig. 37). 
No spirals were found on any of the media. The diameter of the 
filaments varies from 1.0 to 1.3 uw, and the oblong spores measure 
1.6 Xo.8 uy. 
The germination of spores was studied with an oil immersion 
lens, in a hanging drop prepared as follows. A thin film of synthetic 
agar was spread on a thin cover-glass, and a loop full of a dilute 
spore suspension placed on the agar film. This was inverted over 
a dry Van Tieghem cell. The water soon evaporated, leaving the 
spores in contact with the agar, where their germination was 
easily studied and camera lucida drawings made. According to 
DRECHSLER (9), Actinomyces spores produce from one to four 
germ tubes, ‘‘the approximate number being more or less char- 
acteristic of the species.’ This species produces one and two 
germ tubes which often branch directly on leaving the conidium 
(fig. 36). 
The organism was studied in the manner suggested by CoNN 
(3) and Waxksman (33), and the media were made in accordance 
with directions given by WAKSMAN (33). The following culture 
characters were noted: 
CULTURAL CHARACTERS.—1. Synthetic agar: room tempera- 
ture, after ten days: growth densely compact but thalli small, at 
first white, but after ten days Pale Pinkish Buff; aerial mycelium 
white and dense; soluble pigment none. 
2. Calcium malate-glycerin agar: growth spreading and not 
zonated, bordered by submerged mycelial bands of varying width, 
pearl white; aerial mycelium short, loose, and pearl white; soluble 
pigment. 
3. Glucose agar: growth luxuriant, color same as in synthetic 
agar, thallus conspicuously zonated; aerial mycelium white to 
Pale Pinkish Buff, powdery; soluble pigment none. 
4. Glycerin agar: growth densely compact, not zonated, Pale 
Pinkish Buff; aerial mycelium powdery, white; soluble pigment 
none. 
5. Brazil nut agar: growth rapid, densely compact with wide 
margin of submerged mycelium, white to Pale Pinkish Buff; 
