1919] Fernald,— Ranges of Pinus and Thuja 63 
lake. It rises 300 feet above the level of the water and is composed 
seemingly entirely of boulders and drift material” (Camsell, |. c. 146A). 
Hutchinson quotes Bell’s old statement that “there is a remarkable 
outlier of white cedar brushwood around Cedar Lake on the upper 
part of the Saskatchewan River at a distance of 190 miles to the north- 
west of the nearest point of the main area covered by this species.” 
It is, therefore, significant to find Dowling stating that the Devonian 
coralline limestones of James Bay “are similar to rocks of Silurian 
age on Cedar lake in the Saskatchewan district” (Dowling, n. s. xiv. 
36F). And is it not significant, also, that Hutchinson, writing of a 
vast Archaean country should state that “it is notable that through- - 
out great areas, for instance the Temagami region, Thuja is unknown?” 
At this point in his discussion he was near the answer to his problem 
and had he pursued the question with that “notable” fact as a basis 
he would quickly have discovered the truth: that THusa OCCIDENTALIS 
is almost as pronouncedly calcicolous as Pinus BANKSIANA is caleipho- 
bous | 
The impression seems to be very general that Thuja prefers swamps, 
yet it is certainly noteworthy that in really wet swamps it is usually 
only a shrub or small tree, there rarely developing trunks 1 foot in 
diameter. In the area of its best development, the calcareous region 
of northern Maine, northwestern New Brunswick, and the Gaspé 
Peninsula, the splendid trees with trunks often 3 feet in diameter and 
Sometimes twice that size are always on the well drained river-terraces 
or alluvial banks or on rocky slopes. In New Brunswick Ganong 
likewise notes that Thuja “shows a marked dualism of habitat, 
ing most characteristically in low wet places (‘Cedar swamps’) 
but also capable, (at least individual trees are) of existence upon 
upland where conditions approach the xerophytic.”! Similarly 
Professor L. W. Bailey described the Tobique as passing “near the 
base of high and precipitous cliffs of ferruginous rock, overhung with 
cedar”;? in Connecticut two of the three stations are on limestone 
ledges; on the lower Hudson it was “on . . . fine bluffs of paleozoic 
limestone,” and nearly at the southern limit of the species, along the 
Holston River, at altitudes mostly under 1,000 feet, “ especially where 
the banks are rocky and cafion-like . . . . Measurements of the largest 
1 Ganong, Bull. Nat. Hist. Soc. N. B. xxi. 55 (1902). 
*L. W. Bailey, Can. Nat. ser. 2, i. 82 (1864): 
