1916] 
ZELLER—PHYSIOLOGY OF LENZITES SAEPIARIA 441 
recover after four months of desiccation, while Falck (’09) 
found that in one case a sporophore was still feebly viable 
after a year and nine months of desiccation. In my work 
where the tissue method was employed, the sporophores were 
broken open, and small pieces of the tissue from the interior 
were gouged out by means of a sterilized scalpel. These 
pieces of tissue were quickly flamed and transferred to agar 
slants in tubes, after dipping in sterile distilled water to 
moisten. The agar used was Thaxter’s glucose-potato-hard 
agar, made up as commonly employed in this laboratory in 
the following way: Two hundred grams of potato were cooked 
for about one hour in a liter of tap water. The potato water 
strained off was restored to a liter. To this were added 20 
grams of glucose and 30 grams of agar, and the mixture auto- 
claved for 20 minutes to dissolve the agar, which was then 
tubed, sterilized, and slanted. This is a very good medium 
for the growth of Lenzites. 
The tissue transfers grew well, but practically one-half of 
them were contaminated, since diffieulty was found in secur- 
ing a piece of tissue from the interior of such thin sporophores 
without contamination. 
(2) The spore method was more frequently used in this 
work. Buller (’09) discovered the remarkable fact that many 
xerophytie fungi which have been preserved dry for several 
months or even years may be revived by moistening, when 
spore expulsion will be resumed and will continue for several 
days or weeks (according to the specificity of the organism), 
even after the plants have been dried and revived several 
times in succession. In the same year, however, Falck 
reported his work on the desiccation of sporophores of Len- 
ees saepiaria, L. abietina, and L. thermophila, in which he 
used this rejuvenescence due to moisture as an index of 
viability. The spore method is used considerably in forms 
with thin tissues, having been employed by Ferguson (’02), 
Falek (702), Lyman (’07), Münch (709), and others. 
My procedure differs from those of previous workers in 
some details, which are given here. To obtain the basidio- 
