Berry: A NEW MATONIDIUM FROM COLORADO 293 
The accompanying restoration of Matonidium americanum, 
shown in TEXT FIG. 2, is based upon a considerable amount of ma- 
terial which, although fragmentary, supplies data for all parts of the 
frond. Its abundance in the small collection from this one locality 
would seem to indicate that the species was gregarious, sending 
up its stout stipes from a creeping rhizome as does the modern 
Matonia pectinata. The reduced figure was made from a life size 
drawing made by plotting the various fragments of the different 
parts to scale, and the arrangement of the pinnae is based upon 
their disposition in Matonia pectinata and the evidence derived 
from the numerous fossil frond bases (‘‘collars’’) preserved. 
Whether the stipe in the fossil species was as elongated as in the 
modern Matonia pectinata is not known. At the apex the stipe 
of Matonidium americanum was less distinctly dichotomous with 
less scirpoid branches than in Matonia pectinata, one side of the 
stipe becoming concave and the whole forming a reflexed fan- 
like base from which the rachises of the numerous pinnae proceded. 
In life these were not upright as in the restoration but were 
turned back ninety degrees or more giving the fronds an almost 
peltate appearance. 
