INTRODUCTION. XXXVI11 
Pepin, on the Upper Mississippi, of the water-shed which gives origin both to it and 
the Maskeg Fork of Bad River, flowing into Lake Superior. 
It will be perceived that the preceding pages form a synopsis, only, of the conclu- 
sions derived from very extensive observations of the leading features of the coun- 
try explored, unencumbered with details. These details, however, furnishing as 
they do the data whence these conclusions have been drawn, are of paramount 
importance, and constitute, in fact, the body of the Report herewith submitted. 
Being desirous to collect as much general scientific information as possible, with- 
out interfering with the main objects of the Survey, I instructed the members of 
the corps, when not otherwise engaged, to record observations, and preserve speci- 
mens in those departments of natural history in which they were most proficient. 
Accordingly, Dr. Parry, who has a good knowledge of Botany, has reported to me his 
observations made in this branch of science, on the St. Peter’s River, and the country 
lying between the Mississippi River and Lake Superior. Here I shall merely touch 
upon a few of the general results, referring the Department for further information 
to Dr. Parry’s own report. 
Where there is a lithological as well as a paleontological passage from one 
geological formation to another, there is a simultaneous change in the botany of the 
country. This is especially observable in the influence of the trap ranges. The 
vegetation superincumbent on that formation is so marked, that it may often serve 
to detect it when the rocks themselves are hidden from view. 
The drift-deposits of the St. Peter’s support a peculiar growth, among which the 
following are the most striking: Castilliga sessiliflora, Psoralea esculenta (Pomme de 
prairie, or Bread root), Oenothera surrulata, Oxytropis Lambertii, Lygodesmia juncea, 
Orthopogon oligostrachyum. These contrast strongly with the plants which charac- 
terize the drift-deposits occupying the height of land between the Mississippi and 
Lake Superior, which are Pinus Banksiana, Vaccinium tenellum (whortleberry), Gaul- 
theria procumbens (wintergreen), and some species of Lycopodiums, proving a 
decided difference in the two regions, both in the composition of the beds of drift 
and the soil derived therefrom. 
On the shores of Lake Superior, Dr. Parry found a singular blending of littoral 
and Alpine plants, as for instance Lathyrus maritimus (beach pea), and Hudsonia 
encovdes, common to the Atlantic sea-beach, associated with Potentilla tridentata, 
Cenomyce rangiferina, common to Alpine and Arctic regions. These are adduced 
to show the combined influence of soil and atmosphere on vegetation. 
Dr. Parry was instructed to collect as much information as possible with regard 
to the economical and medicinal applications of plants, used by the Indians. 
Several of their most important native articles of food, as he justly remarks, are 
found in regions where we might least expect to find the means of subsistence ; 
thus, the wild rice fringes the innumerable lakes and rivers of this northern Indian 
