28 ROCHESTER ACADEMY OF SCIENCE. [Oct. 8, 



Potamogeton pauciflorus var. Niag- Carex tenuiflora, 



arensis, Panicum agrostoides, 



Eriocaulon septangulare, Panicum Xalapense ? 



Scirpus Clintonii, Triodia purpurea, 



Scirpus Torreyii, Eatonia obtusata, 



Carex oligosperma, Eragrostis Purshii. 



Physical Characters of the Region, 

 by herman leroy fairchild. 



geography and hydrography. 



The territory covered by this list of plants has no natural bound- 

 aries. It includes the county of Monroe and portions of each of the 

 adjacent counties. The arbitrary limits of the map (Plate i) include 

 the western part of Wayne county, the ^vestern half of Ontario, 

 the northern part of Livingston and eastern parts of Genesee and 

 Orleans counties. The northern boundary is Lake Ontario. The 

 43d parallel of north latitude bisects this area, and the meridian of 

 78^ passes through the western portion. The breadth of the area 

 north and south along the western border is 35 miles, and the length 

 east and west is 44 miles. The total land surface is about 1400 

 square miles. 



The drainage is wholly into Lake Ontario. The Genesee river 

 traverses the area of the map in a direction N.N.E. and debouches 

 into the lake near the middle of the north shore boundary. The area 

 includes the hydrographic basin of the lower Genesee from the lake 

 to a parallel five miles above Avon. In the last ten miles of its 

 course the Genesee river occupies a new channel and has no valley or 

 tributaries of consequence, all the northern part of the area draining 

 by numerous streams directly into the lake. The south-eastern side 

 of the area is drained by Mud creek and Canandaigua outlet, the 

 water entering lake Ontario by Oswego river. 



TOPOGRAPHY AND ALTITUDES. 



The area is mostly a plain, sloping gently toward Lake Ontario, 

 The total difference of elevation between the higher ground at the 

 south and the northern edge of the plain at the lake is in general 300 

 to 400 feet. The average altitude of the area is about 600 feet above 

 tide. The middle portion through the whole east and west extent, as 

 traversed by the West Shore and New York Central railroads, has an 



