104 ROYAL SOCIETY OF CANADA 
separated localities which were otherwise characterized by distinctive 
features. 
We must nevertheless not lose sight of the fact that prior to 
Tertiary time, some at least, of the genera now found only in the north, 
had a great southern extension. Thus Sequoia was abundantly repre- 
sented in the Lower Cretaceous as far south as Virginia, and even in 
Texas itself, S. pagiophylloides of the Trinity division gives proof that 
the present northern position of the genus represents a recession since 
Cretaceous time. Cupressoxylon also, is a constituent of the Creta- 
ceous flora as far south as Virginia, and even in more western localities, 
it has been shown to be represented in the Cretaceous of Kansas (12) 
only a few hundred miles to the north of Somerville. There is, there- 
fore, no real reason to suppose that both of these genera may not have 
had their representation in the Eocene of Texas, a possibility which is 
quite in accord with the distribution of Rhamnacinium and Rhamnus 
then and now. This, however, does not imply the actual occurrence 
in Texas of the particular species found in Saskatchewan, and which 
there is reason to believe are northern types, but which are nevertheless 
found to-day in the Yegua clays. 
Our present knowledge of the Cretaceous flora of the United States, 
shows that while the flora of the Lower and Middle Cretaceous was 
that of a warm-temperate climate, there was a conspicuous absence 
of palms which appeared in the later horizons and extended into Ter- 
tiary time. There is, therefore, good reason to suppose that there was 
a progressive change toward a warmer climate from early Cretaceous 
to at least Eocene time, and this theory is borne out not only by the 
occurrence of palm stems in the Yegua clays and overlying deposits, 
but in the actual extension in Eocene time, of the genus Cinnamomum 
into such northern latitudes as the 49th parallel, and we may conclude 
that as pointed out by Kennedy (8), as partly suggested by the floras 
studied by Knowlton and Lesquereux (16), and as now confirmed by the 
present studies, the climate of the Texas Hocene was somewhat warmer 
than at present. 
As bearing upon this conclusion, the evidence afforded by two 
other species from the Yegua clays is of great importance. The occur- 
rence of Laurinoxylon in this horizon and in this locality, points verv 
strongly to more tropical conditions than prevail to-day, and it is quite 
possible that the wood of this genus as now found, may be identical 
with one of the species represented by leaves previously discovered. 
Reynosia, although allied to Rhamnacinium, is nevertheless a distinctly 
southern type. At present it is found only in Florida, the Bahamas, 
Cuba and the Virgin Islands. Its representation in the Eocene of so 
