Macbride: Mountain Myxomycetes 
147 
physarums and their kin abound in the Rocky Mountains about 
Denver and are scarce in the far West. Conversely about Puget 
Sound the trichia and lamproderma types are practically universal 
and dominant. 
A few notes of species, cited in detail, may make this situation 
clear. 
The one calcareous slime-mould everywhere in the west from 
the islands of San Juan to the glaciers of Mt. Rainier is the 
familiar Fidigo, F . septica L., we must finally say. So far as my 
observation goes, in the Washington forest every day from July 
to January, but one phase of the species is to be found, viz. : F. 
ovata Schaeffer. Generally specimens are rather small, but on 
the foot hills of the great mountain they are not only abundant 
but extremely large. On decaying stumps in a hemlock forest 
the yellow plasmodia seemed to aft'ect the landscape, so many of 
them all around, so large, that the foamy plasma might have been 
dipped up with a cup ! 
In contrast with this we have in Colorado three described 
species, and no knowing how many phases of these species, in the 
protean genus. The species are distinguished chiefly by spore- 
characters. Thus, F. septica L. has spores almost smooth, pale 
violaceous 6-7 p ; F. ellipsospora R. has spores ellipsoidal, dark- 
colored, rough, 10-12 p; F. megaspora Sturg., spores globose, 
very dark and rough, 18-20 p. There is still another form re- 
peatedly taken in Colorado with globose spores dark-colored and 
rough, about 10-12 p in size. This is dull gray and fits in be- 
tween the first and third named, and might be called F. media. 
We have in the west beautiful colonies of Lepidodcrma, prob- 
ably L. tigrinum (Schrad.) R. ; in the Rocky Mountain district 
this is reported “ found but once in Colorado.” This is a calca- 
reous type, it is true, but looks rather in the direction of 
Stemonitis. 
But it is in the great genus Physarum itself that the contrast 
becomes more apparent. Here the Colorado lists include some 
twenty-two species to which the Iowa herbarium may add one or 
two. Here is one that we may call Physarum elegans, very much 
like P. pusillum (Berk.) Lister, but with larger, orange or brown, 
short-stalked, sporangia. Here is another that has porcelain-like 
