1919] Fernald,— Ranges of Pinus and Thuja 51 
beech appear also to be more abundant upon the Carboniferous area, 
though common also upon the Silurian uplands. But the striking 
features of the forests upon the latter are the groves and ridges of 
birch and maple occurring in almost every part. These are seldom 
met with on the sandstones except where Lower Carboniferous lime- 
stones prevail. 
“The comparative abundance of ericaceous plants on the Carbon- 
iferous areas is doubtless due, in some measure, to the flat surface and 
consequent imperfect drainage, resulting in the formation of swamps, 
peat bogs, etc., where these forms of vegetation find a congenial 
habitat. But the difference in the sylvan growth occupying the drier 
grounds of the two regions in question is not explicable unless we 
admit that the geological formation has an influence upon it. On the 
sandstone area, the hemlock and scrub pine are most abundant trees 
compared with their distribution upon the Silurian uplands. Black 
birch, beech, and black spruce also appear to be more common and 
larger. These facts regarding distribution lead to the inference that 
the gravelly, siliceous soil overlying the sandstones is more favourable 
to the growth of these trees, or it may be that the limestones are unfav- 
ourable, or, perhaps, both causes operate." (Chalmers, n. s. vii. 140, 
141M). 
Although on the acid north shore of the lower St. Lawrence the 
Banksian pine “occurs abundantly” eastward to “the neighbourhood 
of the mouth of the Moisie River" (Low, n. s. viii. 34L), 1. e. east to 
longitude 66? W., and although it is on thoroughly leached and con- 
sequently acid Permian sands of Prince Edward Island in longitude 
64? W. and on the “ poorest sites in Colchester county," Nova Scotia, 
to longitude 63? W., it is noteworthy that this species should be 
unknown on the calcareous Gaspé Peninsula which in latitude lies 
midway between the “ north shore" and Nova Scotia and in longitude 
fails to reach eastward to the 64th meridian. In his account of the 
limestone region of northern New Brunswick and southern Gaspé 
. (Bonaventure County) Chalmers enumerates the trees “in the order 
of their relative abundance" and, although, as would be expected in a 
calcareous tract, Picea canadensis with trunks 2-23 feet in diameter 
and Thuja occidentalis with trunks 1-3 feet in diameter head the two 
lists, the first for “drier parts of the Silurian upland” the other for - 
the “lower grounds,” Pinus Banksiana is not mentioned at all in 
either list (see Chalmers, n. s. ii. 33, 34M). In an intensive study of 
