122 BOTANICAL NEWS. 
would place the region bordering the Ottawa in nearly the same posi- 
tion with that of the south coast of Labrador fronting on the Gulf of 
St. Lawrence, at present. The absence of all the more Arctic species 
occurring in Labrador, should perhaps induce us to infer a somewhat 
more mild climate than this. 
- The moderate amount of refrigeration thus required, would, in my 
opinion, accord very well with the probable conditions of climate dedu- 
cible from the circumstances in which the fossil plants in question 
occur. At the time when they were deposited the sea flowed up the 
Ottawa valley to a height of 200 to 400 feet above its present level, 
and the valley of the St. Lawrence was a wide arm of the sea, open to 
the Arctic current. Under these conditions the immense quantities of 
drift ice from the northward, and the removal of the great heating sur- 
face now presented by the low lands of Canada and New England, 
must have given for the Ottawa coast of that period a summer tempe- 
rature very similar to that experienced on the Labrador coast, and with 
this conclusion the marine remains of the Leda clay as well as the few 
land mollusks whose shells have been found in the beds containing the 
plants, and which are species still occurring in Canada, perfectly 
coincide. 
The climate of that portion of Canada above water at the time 
when these plants were imbedded, may safely be assumed to have 
been colder in summer than at present, to an extent equal to about 5 
of latitude, and this refrigeration may be assumed to correspond with 
the requirements of the actual geographical changes implied. In other 
words, if Canada was submerged until the Ottawa valley was converted 
into an estuary inhabited by species of Leda, and frequented by capehn, 
the diminution of the summer heat consequent on such depression 
would be precisely suitable to the plants occurring in these de- 
posits, without assuming any other cause of change of climate. 
BOTANICAL NEWS. 
sale 
known 
name of u Tagua." Until now, botanis 
Phytelephas in the province of Panama, 
in the more southern territory of Darien. 
ignorant 
plant was known 
