32 BULLETIN 1053, U. S. DEPARTMENT OF AGRICULTURE. 
on the submerged mycelium after about 10 days, but are empty and 
dead in 2 months. 
The secondary spores of the four species considered here are 
formed on all the nutrient media tried, although in varying quanti- 
ties, but Lenzites sepiaria is the only species so far known to form 
them on wood. Temperature has no appreciable effect on the forma- 
tion of these spores on malt agar. Early in the work it seemed as 
if light favored the formation^ of oidia by Lenzites sepiaria and that 
darkness prevented it. but a variety of tests, variously checked, 
failed to give absolutely consistent results. Yet it was found that 
cultures started in the light nearly always formed oidia. while those 
in the dark seldom did. 
GERMINATION STUDIES OF THE SECONDARY SPORES. 
The oidia of Lenzites sepiaria germinate readily and to practically 
100 per cent on agar. The cylindrical oidia as a rule simply lengthen 
out at either end or both ends with no swelling, so that no sign of 
the original oidium is left (PL III, fig. 11). Germination may be- 
gin, however, with a swelling of the oidium, at one end or in the 
middle, and the germ tube may then arise from either the swollen or 
unswollen ends (PI. III. fig. 9). The club-shaped oidia which are 
found occasionally may send out one or more tubes from either the 
swollen or unswollen ends. In water the tubes are attenuated. The 
chlamydospores of Lenzites sepiaria germinate normally (PL III. 
fig. 10). The oidia and chlamydospores of Lenzites trabea germi- 
nate in a manner similar to those of L. sepiaria. The chlamydo- 
spores of Trametes serialis (PL IV. fig. 9). and Lentinus Jepideus 
send out tubes from either end of the ellipsoid spores, although 
usually from only one end. 
Germination tests were carried out upon the oidia of Lenzite* 
sepiaria and Lenzites trabea and the chlamydospores of Trametes 
serialis. The chlamydospores of L. sepiaria and L. trabea were not 
readily obtainable in sufficient quantities and were hard to separate 
from the oidia. The chlamydospores of Lentinus lepideus could not 
be obtained in a condition which would allow of their manipulation. 
The chlamydospores of all four fungi occur chiefly, if not entirely, 
on the submerged mycelium in the agar. Those of Trametes serialis 
could be obtained in sufficient numbers by scraping the submerged 
mycelium, with as little agar as possible, from the surface of the 
culture, then macerating this material between two thick glass slides 
which had been previously flamed and finally removing this macer- 
ated mixture to sterile water blanks. The chlamydospores were 
separated from the mycelium by this process and the mycelium 
sufficiently injured so that it did not interfere with germination 
