SPECIES OF LENTINUS IN THE REGION OF THE GREAT 
LAKES 
Edward T. Harper 
The species of Lentinus belong to the series of white-spored 
agarics which are tough and leathery and which revive on the ap¬ 
plication of moisture. Their nearest relatives are species of Panus 
and Pleurotus. The species of Lentinus have the edges of the 
lamellae serrate while in Panus they are entire. The character 
represents a difference in the tissue of the two genera. Typical 
species of Lentinus have the gills split and lacerate on the edges 
as shown in Plate XIV, C, not merely rough from an abundance 
of cystidia as is the case in many of the higher agarics. The torn 
edges of the gills are due to the fact that the hyphae run cross¬ 
wise, allowing the gills to split vertically (Plate XIV, A), while 
in Panus the hyphae run more nearly parallel to the edges of the 
gills and allow them to be torn lengthwise. The growth of the 
pileus is more circinate in Panus than in Lentinus. In Panus, 
moreover, the fibers of hyphae are looser and the tissue is more 
homomorphic than in Lentinus. According to Fayod, this fact 
places the species of Lentinus higher in the line of development 
than those of typical Panus. In the genus Pleurotus the tissue is 
still further developed and the plants do not revive on the appli¬ 
cation of moisture. 
The natural home of the leathery species of agarics is in the 
warm regions of the globe. The carpophores dry up and persist 
during the drought and revive in the rainy season. Both Europe 
and the United States are largely north of their zone of greatest 
abundance. Hence the species of these genera in our region are 
fewer and less variable than those of the genera whose natural 
home is in temperate and cold regions such as Clitocybe, Cortin- 
arius, etc. 
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