71 



Of these three, the last plant to be introduced has attained by 

 far the widest distribution, just because it possessed qualities 

 enabling it to thrive and spread. 



Plants Requiring Peculiar (usually Edaphic) Conditions. 

 ■■ — There are several localities in this region where soil conditions 

 are peculiar, and in these places, species, often groups of species, 

 appear that do not occur elsewhere. Peat-bogs, localities about 

 salt springs, marl-formations, and sand-dunes, all have species 

 peculiar to them, and all are represented in the region. Many of 

 the species found in these places are identical with species found 

 along the Atlantic coast, and this led Paine, in his Catalogue of 

 the Plants of Oneida County, page 133, to conclude that "their 

 presence here is proof, first, that the sea originally came up to 

 and covered the place ; and, second, that these plants were flour- 

 ishing at that time." That plant migration may account for the 

 occurrence of these plants inland, is highly probable. Neverthe- 

 less, the number of species involved and the isolation of the areas 

 from the ocean and from each other would seem to lead naturally 

 to Paine's conclusion. Peat-bogs have been the subject of many 

 recent investigations. In the American Naturalist, the writer 

 has discussed the distribution of the peat-bog flora in the Lake 

 Ontario lowlands and pointed out the occurrence in them of a 

 considerable element representing plants of the Atlantic coast. 

 The salt-water plants of Onondaga Lake and Salt Creek, near 

 Montezuma, have been discussed by Clinton, Paine, and others. 

 The flora of the marl-formations of Junius, Seneca County, as well 

 as Bergen Swamp, have been discussed by Judge Day and Pro- 

 fessor Dudley and in the Flora of Monroe County. Nothing has 

 been published on the floras of the sand-dunes at the eastern end 

 of Lake Ontario. The plants and conditions under which they 

 grow are practically identical with the plants and conditions as 

 set forth by Cowles and others in their accounts of sand-dune 

 regions about Lake Michigan. The aflinity of this region to dune 

 regions of the Atlantic coast is obvious, as shown by the presence 

 of a long list of identical species. 



Sylvan Beach in Oneida Lake is an extensive sandy beach on 

 which also occur many of the species found in the sand-dunes of 

 the Great Lakes and the Atlantic coast. 



