1906] KAUFFMAN—A MYCORHIZA-PRODUCING FUNGUS 209 
which are known, Phytomyxa leguminosarum and Frankia are of 
course the most prominent. It will be seen that the list is remarkably 
small, especially if we remember that only one or two species is 
referred to in each case. As we are only concerned with ectotrophic 
forms, the first four can be omitted in the discussion, and if we con- 
sider the evidence on which the symbiotic connection of the remainder 
is based, we find the actual list even smaller. 
In the case of the Boleti, WoRONIN (10), after declaring the tubers 
out of the question, says: “‘Vielleicht gehért die hiesige Mycorhiza 
einem anderen, ebenfalls unterirdischen Pilze an, dies will ich nicht 
bestreiten, bin aber vielmehr geneigt anzunehmen, dass die oben 
angefiihrten Boleten mit der Mycorhizen zusammenhingen.” It 
seems that WorontNn himself was not very certain of the connection. 
Elaphomyces was very exhaustively studied by REES (11), who 
showed that it is undoubtedly connected with the pines in localities 
Where the truffle occurs. Two species of Geaster, G. fimbriatus 
and G. jornicatus, were shown by Noack (13) to be attached to the 
roots of the spruce and pine. 
When we come to a consideration of the agarics our knowl- 
edge is meager indeed. Only one investigator, Noack (13), in 
1889, has concerned himself with them. He found that five species 
of this group were apparently mycorhiza-producers on the forest 
trees of the locality where he made his observations. Two were 
Tricholomas; one a Lactarius; and three were Cortinarii. He 
merely makes the bare statement that they are connected with the 
rootlets by their mycelial strands, which he could easily make out. 
It is very probable that his observations are correct. 
It seems to be appreciated that we need some investigation to 
determine what fungus we are dealing with, so that problems which 
have to do with the physiological side of mycorhiza may be under- 
taken more intelligently; for it is just as likely that knowledge con- 
cerning the fungus and its life history may lead to an understanding 
of the relation of the two organisms as a knowledge of the tree would. 
It seemed worth while, therefore, to report the identity of any such 
mycorhizal fungi whenever the evidence seemed sufficient to make 
It acceptable. 
