222 
M. L. FERNALD 
The localization of plants in the region and the impossibility of 
recognizing the most significant of them from the steamboat, stage- 
coach or railroad-train, is further emphasized by a statement of that 
prince of New England explorers, William Oakes, whose experience else- 
where should have taught him to be more cautious in his drawing con- 
clusions. Writing to his friend Dr. J. W. Robbins on August 14, 1828, 
Oakes said: "The greater part of July I have spent 'down East' even 
as far as Quoddy Head which lieth more eastward than Eastport. 
I have seen there however but few plants new to N. E. and am con- 
vinced that no great accessions to the N. E. Flora, and of absolutely 
new plants hardly any, are to be expected from the State of Maine." 
For this reason, apparently, Oakes, who had visited one of the most 
sterile corners of the state, thereafter avoided the supposedly barren 
state of Maine, the home of the famous crops of Aroostook potatoes, 
and thus missed some hundreds of species which there make up an 
essential element of the New England flora. Even at barren Quoddy 
Head, where Oakes did explore, he failed to detect Iris setosa, then 
known only from Siberia; Comandra livida and Car ex norvegica, Arctic 
species at that time unknown in New England ; and the characteristic 
little Euphrasia purpurea, subsequently discovered and described 
from Newfoundland. 
These illustrations should be sufficient to indicate my point of 
view, that, although the dominant and more or less ubiquitous species 
may serve for the major phytogeographic divisions of a continent, 
they are of little value in the more refined studies of plant distribution ; 
but that it is the relic species now localized in isolated areas which 
give us clues to the long cycles of plant migrations — marches and 
countermarches — which have accompanied the different geological 
epochs since the early Cretaceous; and it is to these relic colonies, 
both of plants and of animals, that the historical geologist must turn 
in the reconstruction of ancient lands now quite obliterated or buried 
beneath the great oceans. And even if we belong to that unimagi- 
native group of botanists who would completely divorce taxonomy 
from other fields of science, we must at least recognize that the dis- 
covery in the indigenous flora of eastern Quebec of plants described 
from Montana, Alaska, or Siberia, or in Alberta or Denmark of species 
first detected about the Gulf of St. Lawrence, forces upon us the 
necessity for caution in characterizing new species. It has been an 
easy principle of convenience but of very unsound scholarship among 
