68 



portions of New York and through nearly all New England, the an- 

 nual rain-fall is from ten to fifteen inches greater. 



The natural botanical district, in which the City of Buffalo is 

 situated, is a part of the basin of Lake Erie. For the sake of con- 

 venience and distinction, it will here be called the Erie District. 



Towards the south and southeast, it finds its boundaries in a range 

 of highlands, distant from thirty to fifty miles from Buffalo, beyond 

 which the streams flow into the Allegany, and thence into the Ohio 

 and the Mississippi. These highlands constitute, in fact, a part of 

 the northeasterly limits of the Mississippi Valley. That region, so 

 far as it comes within the scope of the Catalogue, will be called the 

 Allegany District. 



In Chatauqua County, the limits of the Erie District are very 

 narrow. Between Lake Erie and the head of Chatauqua Lake, the 

 interval of land is but seven and a half miles wide. Here the divid- 

 ing ridge approaches so near Lake Erie as to leave only a strip of 

 land less than four miles in width. Yet the summit of the ridge is 

 891 feet above Lake Erie. Eastwardly its height increases. Between 

 Chatauqua Lake and Connewango Creek the elevation is reached of 

 1401 feet, and between Connewango Creek and Ellicottville, that of 

 1570 feet. Upon the summit, in several places, a conglomerate of 

 the coal period is found, in place. In Chatauqua County, almost 

 upon the crest of the dividing land, a series of lakes appears. The 

 largest of these is Chatauqua Lake, 726 feet above Lake Erie. 

 Northerly and northeasterly from Chatauqua Lake are Bear, Cassa- 

 daga and Mud Lakes, respectively 755, 732 and 833 feet above Lake 

 Erie, and as truly sources of the Mississippi as the far distant Itasca. 



The easterly boundary of the Erie District is another range of 

 highlands, which divides it from the basin of the Genesee River: — 

 here termed the Genesee District. Towards the southeast these 

 elevations meet and unite with those which separate the Erie from 

 the Allegany District, and are as high. To the north they decline, 

 but even at Batavia they have an elevation of about 300 feet above 

 Lake Erie. 



The northerly boundary of the Erie District is marked, both in 

 New York and Canada, by that extraordinary exposure and eleva- 

 tion of rock, known in its vicinity as the " Mountain Ridge," and to 

 which Canadian geologists have given the name of the " Niagara 



