FUNGI OF IMPORTANCE IN THE DECAY OF TIMBERS. O 
METHODS USED IN THE BASIDIOSPORE STUDIES. 
The basidiospores used in the tests were collected and kept on 
sterilized glass slides, as a rule, although the spores of Lent'tmis 
lepideus were collected upon sterilized black paper. The spore 
prints were obtained in the usual way. care being taken to prevent 
moisture from collecting upon the prints for it was found early in 
the work that such condensation water affected the viability of the 
spores. The prints were then preserved in Petri dishes in an ice 
box in which the temperature was 12° to 16° C, and the relative 
humidity 40 to 45 per cent. For the general purposes of experi- 
mental work the glass slides for spore prints were preferred to the 
black paper because of ease of manipulation and cleanliness. 
All spore germination tests were made upon the surface of agar, 
usually in Van Tiegheni cells. The germination of spores upon the 
surface of the cooled agar had certain advantages. The question 
of the oxygen supply available for the spores was obviated. It was 
easier to count percentages of germinated spores when they were all 
in one plane. And besides there was no danger of subjecting the 
spores to unfavorable temperatures, as may be the case when they 
are introduced into melted agar. A temperature only slightly too 
high, produced either by a hot needle or hot agar, materially reduces 
the percentage of germination. For purposes such as drawing, 
photography, or examination b}^ the higher powers of the microscope, 
sowings of spores were made upon thin films of agar poured on 
sterile slides kept in moist chambers under sterile conditions. The 
agar media used for all experimentation contained 2 per cent of 
agar with 24 per cent of malt extract, filtered through filter paper in 
a Buchner filter and autoclaved 30 minutes at 8 pounds pressure. 
Occasionally, for the taking of photomicrographs, water agar (malt 
extract omitted) similarly filtered Avas used because of its greater 
transparency. Unless otherwise specified, all germination tests were 
run in an incubator at 28° C. 
GERMINATION OF THE BASIDIOSPORES. 
The germination of the basidiospores of the species under con- 
sideration presents no features unusual for hyaline hymenomycetous 
spores. All of them swell more or less in the process. The spores 
of Lenzites sepiaria, L. trobea. and Lentimis lepideus swell to very 
little more than the diameter of the germ tube, so that they are not 
very conspicuous in the thalli of the germinated spores (PI. III. 
fig. 1: PI. IV, fig. 1; PI. V, fig. 2). Fomes roseus spores swell con- 
siderably (PI. V, fig. 1), but those of T rometes serialis swell much 
more (PI. IV, fig. 5). These latter spores swell to a large globular 
body of many times the volume of the original spore before the germ 
