1921] SPENCER—BRAZIL NUTS 275 
the central portion becomes green, and a few days later turns sooty 
black. The thallus then is made up of three concentric rings, the 
outer white, the next green, and the innermost black (fig. 11). 
As the thallus ages it shows marked zonation, and becomes entirely 
black when growth ceases. Aerial mycelium is produced on all 
parts of the thallus, but is most luxuriant in the central area. On 
Brazil nut agar the growth is very much slower than on cornmeal 
agar, usually 0.3 mm. per day at room temperature, and the en- 
tire thallus remains hyaline. On nut plugs the growth was very 
weak, but a crust similar to that of naturally diseased nuts was 
formed after three months. On autoclaved rice the growth was 
vigorous, and several characteristic color reactions were noted 
(fig. 8). Eight days after inoculation: aerial mycelium snow white 
with line of Antique Green’ below; rice grains in contact with 
glass, white bordered with Cerulian Blue; all interstices with 
greenish tints. After fifteen days: aerial mycelium white with 
lower border line Prussian Blue, almost black; contacts of grains 
with glass white bordered with Prussian Blue; interstices purple 
tinged. 
The hyaline immature spores as well as the black mature ones 
germinated readily. The immature spores occasionally germinated 
in ten minutes after planting, while more than an hour is required 
for the germination of the mature spores, but the germ tubes of the 
mature ones soon outstrip those of the immature (figs. 16, 17). 
There is no change in either spore, except a slight swelling in 
germination, the immature spore remaining unicellular. This phe- 
nomenon of the germination of immature as well as mature spores 
has been pictured by Hicerns (11) for a related species. 
TAaxoNnomy.—The morphological characters of the fungus are 
those of Pellioniella Sacc., but according to SACCARDO (25) there 
is but one species in the genus, P. deformans Penz. and Sacc., 
whose spore measurements are a little more than half those of the 
Brazil nut parasite. The fungus, therefore, is given the name 
Pellioniella macros pora. 
* The nomenclature used in describing colors throughout these investigations is 
that given in Ropert Rmwceway’s Color standards and color nomenclature, pub- 
lished by the author, Washington, D.C. ror2. 
