THE BRYOLOGIST. 
Vol. X. 
March, 1907 
No. 2. 
FURTHER NOTES ON CLADONIAS. IX. 
Cladosm squamosa and Giadonia subsquamosa. 
Bruce Fink. 
As promised in the last paper of this series (Bry. 9; Nov., 1906) the 
species to be considered next in order is Cladonia squamosa. A somewhat 
close relationship seems to exist between this species and two of those con- 
sidered in the last paper, viz Clado.nia caespiticia and Cladonia delicata . 
When we consider the differences that appear in the horizontal thalli of the 
three species, we can hardly think that we have a possible immediate gen- 
etic line in these species, but the relation is close enough to cause frequent 
confusion on the part of persons reasonably well acquainted with lichens. If 
the considerations below and preceding, with the accompanying figures, aid 
in alleviating the difficulties encountered in the study of these plants, the 
writer will have accomplished his purpose. 
The close relationship between Cladonia squamosa and Cladonia sub- 
squamosa is generally admitted by lichenists, and the two species are there- 
fore considered in succession in the present paper. 
There is still one other difficulty that will be met in the study of Cla- 
donia squamosa, and that is confusing certain forms of this species with 
forms of Cladonia furcata. The squamules, both of the primary thallus 
and the podetia, should furnish sufficient means for differentiation, to say 
nothing of the podetia, and yet the separation is not always easy to make. 
As good cladoniologists as Dr. Wainio and L. Scnba failed to agree on a 
form of Cladonia furcata collected by the writer at Fayette, Iowa. Mr. 
Scriba thinking it might be a form of C. squamosa rather than C.furcata y 
but surely all one species, and Dr. Wainio thinking from the material exam- 
ined that both species were represented in the material sent. Repeated' 
studies at the spot where the plant grows fully convinced the writer that all 
belonged to the one species. C. furcata. A considerable portion of this, 
material is still in the writer's herbarium, and specimens will be sent to any 
persons sufficiently interested to send for them. 
Cladonia squamosa (Scop.) Hoffm. Deutschl. FI. 2: 125. 1796. Primary 
thallus commonly persistent, composed of middling sized or rarely large, 
crenate, irregularly-subdigitate or subpinnate-laciniate squamules, which 
are 1.5-7 mm. long and 1-5 mm. wide; ascending, flat or involute; scattered 
or clustered and rarely cespitose so as to form a compact crust; sea-green 
varying toward ashy or brown above: below white; the cortex continuous. 
Podetia arising from the surface of the primary thallus, rarely dying at the 
base; 10-85 mm. long and 2-5 mm. in diameter: subcylindrical or rarely 
trumpet shaped; irregularly turgescent; clustered, erect, ascending, decum- 
bent or irregularly flexuous; rarely simple or commonly more or less irregu- 
larly or radiately branched, the branches erect or spreading, the axils fre- 
The January BRYOLOGIST was issued January 2, 1907. 
