628 THE FRESH- WATER LOCHS OF SCOTLAND 
of temperature of only about 10 degrees Fahrenheit. Marsh ^ has 
made a special study of the fauna of this lake, and says that 
in general character it resembles that of the Great Lakes. Green 
Lake is taken as a type of a deep lake, and Lake Winnebago, 
about ^5 miles east of it, drained by the Fox River, as a type 
of a shallow lake. 
Lake Winnebago is about 28 miles long, by 8 to 10 miles broad. 
There has never been an accurate hydrographic survey of the lake, 
but it is probable that it is nowhere over about 25 feet deep. The 
water of this lake is very much discoloured during most of the year, 
and owing to its shallowness storms disturb it to the very bottom 
over the greater part of its area, with the result that during summer 
it has a nearly uniform temperature from top to bottom, becomes 
warmed early in spring, and cools off with corresponding rapidity in 
autumn. 
Lake Champlain. — To the south of the St Lawrence estuary, 
in the basin between the Adirondacks and the Green Mountains, 
extending a short distance into Canada, lies the valley of Lake 
Champlain, the geographical history of which is exceedingly remark- 
able, for this fresh- water lake was originally a well-developed river 
valley excavated by a stream tributary to the Greater St Lawrence 
when the land stood higher than now. After acquiring its present 
form the Champlain valley was depressed and became an arm of 
the sea, inhabited by marine molluscs and frequented by whales. 
A tideway reaching southward connected with the submerged Hudson 
River valley, thus making New England an island. A partial re- 
elevation of the land caused the gulf to be separated from the ocean, 
so as to form a saline lake, the salt waters of which were ultimately 
flooded out, the rains and feeding streams furnishing a supply of 
fresh water in excess of the amount lost by evaporation. Elevated 
strands with recent fossil remains indicate the former great extent of 
the lake. The lake now drains into the estuary of the St Lawrence by 
the Richelieu River, and is connected with the Hudson River by the 
Champlain Canal. The length of Lake Champlain is about 125 miles, 
its maximum breadth about 15 miles, its area 595 square miles, its 
greatest depth 600 feet (Emmons), and its height above sea-level 
93 feet. 
Lake George (sometimes called Horicon), a long and narrow lake 
of New York, forms part of the boundary between Warren and 
Washington counties. It lies 325 feet above sea-level, covers an area 
^ See " Limnetic Crustacea of tlie Great Lakes," Trans. Wisconsin Acad. Sci., 
Arts, and Letters, vol. xi. p. 179, 1897 ; also "The Plankton of Lake Winnebago 
and Green Lake," Wisconsin Geol. a7id Nat. Hist. Survey, Bull. No. xii,, Scient. 
Series, No. 3, p. 1, 1903. 
