22 BULLETIN 1053, U. S. DEPARTMENT OF AGRICULTURE. 
quite abundantly throughout the flasks. The mycelium of Lentinus 
lepideus covers the individual blocks with a bunchy, uneven growth, 
while that of Trametes serialis forms a thick, even growth over the 
whole mass of blocks. Yet the mycelium of the former fungus binds 
the blocks quite solidly together, so that it takes some little effort 
either to remove individual blocks from the flask or to loosen the 
mass for emptying the flask, while the more pronounced mycelial 
growth of Trametes serialis does not have such a binding effect. The 
aromatic odor mentioned is much more pronounced in the flask block 
cultures; the other four fungi here studied do not produce such an 
odor. 
MICROSCOPIC CHARACTERS OF THE MYCELIA ON MALT A GAR. 
Lenzites sepiaria: 
Secondary mycelium- 
Submerged. 
Colorless, avellaneous in mass ; 1.5 to 4.6 /* 4 , most 2.5 to 3.2 fi ; 
septa fairly abundant ; branching not abundant ; clamps not observed ; 
chlamydospores and oidia found occasionally on submerged mycelium, 
the latter chiefly in agar drop cultures. 
Aerial. 
Colorless; chiefly short, branched hyphse which break up more or 
less completely to oidia ; size same as submerged ; septa fairly 
abundant; no clamps observed. Oidia colorless, mostly ellipsoid- 
oblong, occasionally ellipsoid, ovoid, globose, pyriform, or clavate, 
occasionally septate; terminal oidia usually clavate; 2.5 to 3 /» X 
4 to 35 fi ; helicoid hyplue present, but not abundant. 
Tertiary mycelium (aerial) — 
Seldom noted in the writer's single-spore cultures. In cultures from 
sporophores, more abundant; long, stiff, hairlike, sparingly branched, 
septa not abundant, clamps at septa. 
Lenzites trabea: 
Secondary mycelium — 
Submerged. 
Colorless; 1.5 to 3 n ; irregular; branching, clamps, and septa 
abundant; chlamydospores much less abundant than the oidia, thin 
or thick walled, terminal or intercalary, ovoid to globoid, 6 to 8 X 
8 to 18 fi. 
Aerial. 
Colorless ; 1.5 to 3 m; branching common, usually at right angles ; 
clamps and septa fairly abundant ; oidia abundant, mostly cylindrical 
to ellipsoid-oblong, terminal ones ovoid to pyriform and clavate or 
even globoid, 2 to 8 X 6 to 24 /x, mostly about 5 X 10 jtt. 
Tertiary mycelium (aerial) — 
Colorless, slightly yellowish in mass; long, straight, and stiff; branch- 
ing and septa not abundant; clamps fairly abundant; no oidia or 
chlamydospores observed. 
* The figures in these descriptions refer to the range of measurements observed during 
ordinary examination. 
