Summary Narrative of an Exploratory Expedition to the Sources of the Mississippi River, in 1820 / Resumed and Completed, by the Discovery of its Origin in Itasca Lake, in 1832

by Henry Rowe Schoolcraft

26. Unio complanatus, Lea. U. purpureus, Say. Lake Vaseux, St. Mary's River. Lake Vaseux is an expansion of the River St. Mary, a tributary of the upper lakes. This shell does not appear to exist in any of the streams flowing into the Mississippi.

27. Unio crassus, Say. Upper Mississippi, Prairie du Chien.

28. Unio radiatus, Barnes. Lake Vaseux. The specimen is old and imperfect, but I believe it to be the U. radiatus of our conchologists, which is common in Lake Champlain and also inhabits the St. Lawrence.

29. Unio occidens, Lea. U. ventricosus, Say, Am. Con. U. ventricosus, Barnes? Wisconsin and St. Croix Rivers, and Shell Lake. Epidermis variously colored, and marked with numerous rays.

30. Unio ventricosus, Barnes. Upper Mississippi, from Prairie du Chien to Lake Pepin and Shell Lake. The varieties of this, and the preceding pass insensibly into each other. Those from Shell Lake are of extraordinary size.

31. Unio alatus, Say. Symphynota alata, Lea. Upper Mississippi, and Shell Lake. Found also in Lake Champlain, by the late Mr. Barnes.

32. Unio gracilis, Barnes. Symphynota gracilis, Lea. Upper Mississippi, and Shell Lake. The specimens brought by Mr. Schoolcraft are larger and more beautiful than I have seen from any other locality.

VI.
BOTANY.

1. A List of Species and Localities of Plants collected in the Northwestern Expeditions of Mr. Schoolcraft of 1831 and 1832. By Douglass Houghton, M. D., Surgeon to the expeditions.