_Cassina_ or _Red Cedar Lake_ derives some importance from having been designated as the true source of the Mississippi river. It is about eight miles long and six in breadth, and presents a beautiful sheet of transparent water. On its banks are elm, maple, and pine trees, fields of Indian rice, rushes and reeds; in other places there is an open beach of clean pebbles. Pike, carp, trout and cat-fish are caught in its waters. Towards its western extremity is an island covered with trees, from which it derives its name, though no red cedar is found around its shores. _Turtle Lake_, _Little Winnepeg Lake_, _Leech Lake_, _Swan Lake_, _Sandy Lake_, _Muddy Lake_, _Lake Peckagama_, and _White Fish Lake_, are all near the source of the Mississippi. A narrow belt of high land separates Turtle Lake, the most northern source of the Mississippi, from _Red River Lake_, one of the sources of the Red river which runs into Hudson’s Bay. _Otter Tail Lake_ is the most southern source of Red river; and from thence is a portage of only half a mile to a branch of Raven river, which falls into the Mississippi. The whole tract of high country, at the sources of the Mississippi and Red river, is full of marshes, morasses, and small lakes, whose waters afford never failing supplies to these streams. The _Lake of the Woods_ is of a circular figure, with a cluster of islands in the centre. The navigating course through the lake, is seventy-five miles; but, in direct distance, it is not above two-thirds of that extent in diameter. Its scenery is wild and romantic in a high degree. Its surface is covered with islands. From this lake there is a long succession of small lakes, and numerous portages, to the north-west end of Lake Superior, the chief of which is _Rainy Lake_. Two small lakes, _Lake Biddle_, which gives rise to the Big Horn river, and _Lake Eustis_, which is the source of the Jaune, or Yellow Stone river, are situated amongst the Rocky Mountains, in west longitude one hundred and twelve degrees, and north latitude forty-two degrees.