Jan., 1915.] 
Plant Distribution in Ohio. 
411 
According to Merriam, the northeastern part of Ohio belongs 
to the Transition Zone and all the rest of the state to the Upper 
Austral Zone. 
In map I are indicated some of the more important physio¬ 
graphic lines in Ohio as follows: 
a-a, Western boundary of the Alleghany Plateau, following 
closely the eastern limit of the Ohio Shale. 
b-b, The terminal moraine or glacial boundary. 
c-c, Lake Erie Ohio River divide. 
d-d, North-west beach of glacial Lake Erie; the country 
beyond this is deeply covered with drift underlain with 
shale. 
e, Edge of the higher hill country. 
According to all the data available and the lists of plants 
given below, Ohio apparently falls into four general regions or 
areas and for a preliminary survey seven natural plant regions 
may be recognized. These areas will at present not receive 
final, distinctive phytogeographic names but be indicated simply 
by their physiographic character or their geographic position as 
follows: (See Map II.) 
I. Glaciated Alleghany Plateau, belonging to the “Tran¬ 
sition Zone.” 
II. Non-glaciated Alleghany Plateau, eastern division, 
including most of the Muskingum river basin, and the 
counties to the east. 
III. Non-glaciated Alleghany Plateau, western division, 
containing the highland between the Muskingum and 
Scioto. 
IV. The Miami Area, mainly a glaciated calareous region. 
V. The Great Black Swamp Area and contiguous country. 
VI. The Williams County Area. 
VII. Sandusky Bay and Lake Erie Islands Area. 
The seven areas may be briefly delimited and characterized 
as follows:—■ 
I. The Glaciated Alleghany Plateau has its southern bound¬ 
ary in the terminal moraine and its western boundary at or a little 
beyond the limits of the Appalachian highland which approaches 
the eastern line of the Ohio Shale. As stated this area is recog¬ 
nized as a part of the Transition Zone of Merriam. Interesting 
plants found in this part of the state are: 
Pinus strobus 
Calla palustris 
Xyris flexuosa 
Lysias orbiculata 
Pyrola secunda 
Andromeda polifolia 
