492 GriIGGS: THE SUGAR GROVE FLORA 
Each of these when the whole range of the plants concerned is 
taken into consideration is found to be a composite of several types 
of distribution. These together with others belonging to types 
not so conspicuously homogeneous within the state may be 
classified as follows: 
A. ALLEGHENIAN PLANTS ON THE SOUTHWESTERN EDGES OF 
THEIR RANGES. 
Type range, BETULA LUTEA (FIG. 3). 
by Ca 
of 
yt <= 
J 4 
BY ta (ae é 
a wee r ° 
a 
pa 
. 
a & 
— Oo Xo) ps, yo 
A 
s eg 
ye % 
I bY 
Fic. 3. Range of Betula lutea, 
This list includes beside the Alleghenian plants which go no 
further west than the Lake Superior region, some Canadian 
plants which stretch across the continent. Though these are 
more northerly and fewer of them reach Ohio, the ranges of those 
that we do have are so similar to the Allegheny type that they are 
inseparable. Capnoides sempervirens (FIG. 4) and Cornus canadensis, 
which terminates about twenty miles north of our area, are typical 
examples. Although this is a very homogeneous group of plants, 
conforming very closely to the typical range, many of them are 
also found in outlying stations far removed from the main range, 
as for example Blephariglottis lacera and Tsuga canadensis. There 
is also a tendency which may become more evident when more 
cdllections are available, for some of them to extend into south- 
western Ohio and southern {Indiana, e. g. the chestnut. This 
list includes 39 species as follows: 
