{PENHALLOW] A REPORT ON FOSSIL PLANTS 293 
is of Mesozoic age, nor with any of the various species of Sabal, which 
have been described as occurring in the Cretaceous and Tertiary. Under 
these circumstances, it seems altogether probable that the various ridges 
are not original features of the organ, but that they have been produced 
by certain conditions of preservation, and that their regular occurrence 
at stated intervals is only an expression of the location of the principal 
nerves or veins. On the basis of this interpretation we must conclude 
that these fragments cannot be definitely separated from those repre- 
senting Cyperacites haydenii, with which they must therefore be 
regarded as identical. This conclusion also gains strength from the 
271 
1, 23.3 
a character as to readily show how the one passes into the other by vary- 
ing conditions of preservation. 

circumstance that specimens present intermediate forms of such 
271 250 : : : 
of 1903 and aa Cc “a. of the previous report incorrectly given). 

4, 1U 
CYPERACITES, sp. 
Various fragments of an endogenous leaf, which it has been cus- 
tomary to refer to the genus Cyperacites without any specific designation, 
because the details of form and structure are usually so altered as to 
make identification impossible. No. 4, nevertheless shows the details 
of the venation much more perfectly than is commonly the case. The 
whole fragment is 1.5 em. broad and 8.2 cm. long. The very prominent 
and parallel venation is found to show about 9 veins to the cm., but 
this is only approximate, since it is found that owing to a collapse 
of the general structure, some veins are much nearer than others. 
Their normal interval would seem to be about 1 mm. In specimens 
1007 
3a. & 6a 
fall under the same generic designation. 
Remains of this character are of very common occurrence through- 
out the Tertiary, and Dawson (5) has even recorded under this name, 
a specimen which he describes as “A slender. grass-like stem with 
linear, finely striate leaves, alternately disposed and not proceeding 
from enlarged joints.” In his account of the Flora of the John Day 
Basin in Oregon, the horizon of which is regarded as Upper Miocene, 
Knowlton (34) records the occurrence of a stem showing parallel vena- 
tion, the whole specimen corresponding in all its details to that which 
has been described from the 1903 collection under number ae 
, precisely the same forms recur, and they must be held to 
