456 
A tentative attempt has been made to correlate the distribu- 
tion of the following ferns with the faunal distribution as worked 
out by Dr. J. Allen (Geographical Distribution of North American 
Mammals, Bull. Amer. Mus. Nat. Hist. iv. 199-244 (1892)), and I 
have used the terms applied by him there to faune for flore. In 
the main, the distribution of ferns appears to agree with that of 
mammals, but there seem to be some discrepancies which further 
observations may tend to reduce. 
Dr. Allen has divided and subdivided the faunal areas of North 
America into Realms, Regions, Subregions, Provinces, Subprovinces, 
Districts and Faune. The latter only need concern us at present, 
and of his eleven faunz four cover the territory under considera- 
tion. These are known as the CANADIAN, the ALLEGHANIAN, the 
CAROLINIAN, and the LouIsIANIAN, and their geographic limits in 
the following lines are taken from Dr. Allen’s paper already men- 
tioned; however, their western portions are not considered here. 
1. The CanapiAN Fora includes the northern half of New 
England, Northern Ontario, New Brunswick, Quebec, and the 
southwestern angle of Newfoundland. In addition to this more 
or less connected area, it is represented by detached tracts of 
greater or less extent along the summits of the Appalachian 
Mountain System as far south as Georgia. 
2. The ALLEGHANIAN Frora is bounded on the north by the 
Canadian, and on the south by the Carolinian. It runs southward 
as an irregular belt on the upper slopes of the mountains, separat- 
ing the Canadian from the Carolinian. 
3. The Carouinian Fiora meets the Ad/leghanian on the abies 
in Pennsylvania, New York and New Jersey, and doubles the moun- 
tain system where the latter runs out in Northern Alabama and 
Georgia. It passes into the plains on the west and on the east 
descends into the pene-plains, reaching the Atlantic Ocean from 
Virginia to New York, and separated from the water from Vir- 
ginia southward by the Lowiszanian. 
4. The Louisianian Fora includes all the Southern States 
south of the Carolinian except the extreme end of South Florida. 
Now, what I hope to be able to work out in the future is: 
1,—how far the Canadian flora descends down the slopes from the __ 
- summits of our highest mountain peaks ; 2.—at what altitude the : 
