8 ARKIV FÖR BOTANIK. BAND ll. w:o 3. 
to settle the many doubts it seems quite necessary to make a 
thorough study of those plants just on the spots from where 
the authors obtained the specimens on which the descriptions 
are based. 
For these reasons I must defer the treatment of Agarica- 
ceae to another time and begin with the Polyporaceae, which as 
a rule are less destructible so that they can generally be recog- 
nized also in the dried state, especially if spores from a fresh 
specimen are collected on a glass and saved for comparison. 
Such precaution should always be taken, as it is often very diffi- 
cult or even impossible to get spores in quantity from dry spe- 
cimens, especially if they have been kept dry a considerable 
time. And when spores are found only sparingly, they must 
be considered doubtful, as spores or sporelike bodies from other 
sources or of other nature are often intermixed, a circumstance 
that has caused many mistakes and many wrong statements." 
It is well known that one and the same name is often 
used for different fungi by different authors, so that the mere 
statement of a name will not always be sufficient for identifi- 
cation. And the addition of an author’s name to the name of 
the plant will generally not exclude the ambiguity as even the 
sense in which an author used his plant names is often subject 
to different opinions, when the descriptions are vague and 
authentic specimens are missing or not adapted to remove the 
doubts. 
And therefore in order to make it possible to see which 
plant I mean under the names used, I have found it indispen- 
sable in many instances to add some characters. In some in- 
stances I have added also photos of the plants or microphotos 
of the spores. These microphotos are all taken on the same 
scale so as to facilitate comparison. TI used a common lens of 
Harrnack No. 7 with ocular No. 2, the latter at a distance of 
35 cm. from the photographic plate and with a camera lens of 
GoERZ Ser. III: 1 interposed in close proximity to the ocular. 
The latter being provided with a scale, the intervals of which 
correspond to 3 v», anyone can control the sizes. The spores 
are photographed in diluted solution of sodium-carbonate. The 
other photos are all in natural size. 
1 Dried specimens recently collected can give off spores abundantly if 
the specimens are moistened by placing on them wet bits of blotting paper or 
the like. But after a month or two this quality is generally lost. 
