[ PENHALLOW] A REPORT ON FOSSIL PLANTS 3831 
Aspidium fredericksburgense, Font., is an exceedingly well char- 
acterized plant, and there can be little doubt that the same species 
occurs in the flora of the Skagit river district. It was originally 
described by Fontaine (19: p. 94, pl. xi and xii), from the Potomac 
formation at Fredericksburg, Virginia, where it is said to be one of the 
most common ferns. 
Reviewing this evidence, we observe that there are eleven species 
of plants from locality 1430. Of these Dorstenia (?), which is of 
questionable character, and Pinus, which is chiefly represented by seeds 
and may indicate any one of several horizons, need to be eliminated 
because not specifically defined. This leaves nine well-defined species, 
of which three are definitely Lower Cretaceous and six as definitely 
‘Upper Cretaceous. These differences, however, are fully in accord 
with the correlations already established by Dawson (9: iv, 19), and 
by Diller and Stanton (17: p. 476; and 18: p. 435, etc.), and we may 
conclude that at least that portion of the flora from the Skagit river 
which is embraced in locality 1430, is of Shasta-Chico age, and that it 
shows two well defined horizons within that series. 
Directing attention to locality 1428, about which a specific question 
was raised with respect to its age relatively to that of 1430, it is 
possible to give a very definite answer. This locality has furnished 
four specimens of plants only. Of these one species of Salix presents 
nothing in the nature of reliable evidence, and it shows no contact with 
the other localities. Pinus is represented by fragments of leaves and 
seeds which also appear in locality 1433, which is presumably of the 
same age. Glyptostrobus, bearing a certain resemblance to G. euro- 
pæus, appears only in this locality, and it may or may not be comparable 
with G. gracillimus, Lesq., which Dawson has described from the 
Niobrara horizon of British Columbia (Oil) sR bab. ay 
be recalled that Dawson (9: iv, 25) directs attention to a species of 
Glyptostrobus from the Upper Cretaceous of Vancouver Island, which 
he refers to as comparable with G. europæus in form and size, but too 
obscure for certain determination. Furthermore, Knowlton (37) enu- 
merates nine species of Glyptostrobus, of which five are Cretaceous, 
chiefly from the Kootanie and Potomac series, while one of these, 
G. greenlandicus, Heer, is also found in the Kome beds of Greenland 
(21: p. 76). Our present specimen, therefore, is of generic value 
only, and its presence might support any Cretaceous horizon. Under 
these circumstances our knowledge of the actual age of 1428 must be 
based wholly upon the evidence afforded by Gleichenia gilbert-thompsoni. 
This plant was originally obtained from the Lower Cretaceous of the 
