354 



NATURALIST'S GUIDE TO THE AMERICAS 



animals native to this section. 800- 

 1300 ft.; abrupt. 



Torrent^. (B3.) 3| mi. north, Lex- 

 ington and Eastern R. R.; Glencairn, 

 north to Mill Creek, east to lower end of 

 "Tight Holler" (w). Or, Torrent, 5 mi. 

 north, L. & E. R. R.; Campton Jet.; 

 east, about 15 mi. on narrow gage to 

 Pine Ridge; the one mile across upland 

 to faint trail leading into head of "Tight 

 Holler." Wolfe County, Ky. E. L. 

 Braun. 



11. OHIO 



BY E. LUCY BRATJN AND 

 LYNDS JONES (Birds) 



LOCATION AND EXTENT 



The area of Ohio is 41,240 sq. mi. It 

 extends from about 38 30' N. latitude 

 at the most southerly bend of the Ohio 

 River, nearly to 42 N. in the northeast 

 corner; and from 80 30' to 84 45' west 

 longitude. The Ohio River forms the 

 entire southern and part of the eastern 

 boundary; Lake Erie, most of the 

 northern boundary. These natural 

 boundaries are to some extent biological 

 barriers. 



CLIMATE 



The climate is fairly uniform over the 

 entire state. As Ohio lies in the path 

 of most of the cyclonic storm areas 

 which pass across the country from west 

 to east, its temperature, precipitation, 

 sunshine and cloudiness, are largely 

 affected by the passage of "highs" and 

 "lows." Slight differences in tempera- 

 ture in a north-south direction may be 

 noted. Lake Erie has a decided influ- 

 ence on the temperature of a narrow 

 belt near the lake, increasing the length 

 of the period between the last killing 

 frost of spring and the first killing frost 

 of autumn from one to two months. 

 The mean annual temperature for the 

 period from 1883 to 1910 is 50.7F. 

 The mean temperature for July is about 

 73; for January, about 28. The ex- 

 treme annual range of temperature for 

 the state is about 150. 



The average annual precipitation for 

 the state is about 39 in., fairly evenly 

 distributed through the year. Extremes 



of 20.2 in. in 1856 and 50.33 in 1890 are 

 recorded. The river counties of the 

 southeastern part of the state and the 

 northeast corner have the highest rain- 

 fall averaging 40 in. or more; the 

 western lake counties and the upper 

 Maumee basin have the lowest 34 in. 

 or less. 



PHYSICAL FEATURES 



Altitude. The altitudinal range in Ohio 

 is scarcely more than 1100 ft. The 

 lowest land in the state, in the southwest 

 corner, is 420 ft.; the highest, in Logan 

 County near Belief ontaine, is 1540 ft. 

 The eastern and southeastern part, 

 and the west central counties, contain 

 most of the highest land, a considerable 

 area lying between 1000 and 1500 ft. 



Drainage. About five-sevenths of the 

 state lies in the drainage basin of the 

 Ohio, the remainder in the St. Lawrence 

 basin. The divide between the two 

 drainage basins is well north of the 

 center of the state, and in its eastern 

 half approaches close to Lake Erie. 

 The headwaters of the larger north- 

 flowing and south-flowing streams are 

 very close together. Most of the state 

 is fairly well drained; swamps are 

 neither extensive nor numerous, and 

 natural lakes are few. Streams have cut 

 their valleys in a former plateau, and 

 valleys are everywhere narrow, and 

 bottomlands not extensive. 



Glaciation. The surface features of 

 about three-fourths of Ohio have been 

 modified by glaciation. In addition to 

 the lacustrine deposits of glacial Lake 

 Maumee, in the northwest part of the 

 state, three glacial deposits are ex- 

 posed the Late Wisconsin, the Early 

 Wisconsin, and the Illinoian. The Illi- 

 noian drift is covered with a deposit of 

 loess. 



Of the unglaciated part of Ohio, all 

 except a small area in Brown and Adams 

 Counties along the Ohio River, is in- 

 cluded in the "hill country." 



PHYSIOGRAPHIC PROVINCES 



The western half or more of Ohio is 

 underlain by limestones and shales, 



