94 
Terms of frequency, such as rare, occasional, common, and abundant, 
are self explanatory. For further notes upon the relative abundance of 
many species reference should be made to the general description of the 
vegetation given elsewhere by the writer. Terms descriptive of habitats 
also need little explanation, but a few notes will make for clarity. Upland 
denotes all of the area above the recent flood-plain and delta deposits of 
the main rivers, and includes the rocky hills in the lowland flood-plains 
also. Rich woods usually denotes a spruce timber with a thick mat of 
mosses and very little undergrowth. Muskeg timber is the black spruce 
forest that develops in old muskegs. Open woods refers to the upland, 
park-like, jackpine or poplar timber that is so common in the area. Slough 
and wet s meadow are used rather interchangeably to denote a wet depres- 
sion covered with sedges and grasses. A muskeg is an undrained depression 
whose cover consists largely of mosses, of which Sphagnum is the com- 
monest. 
The few notes on poisonous plants are derived largely from Dr. L. H. 
Pammel’s exhaustive manual (46). A few notes upon this subject and also 
upon the edible qualities of certain species are from James R. Anderson’s 
studies in British Columbia (1). 
The order and definition of families is that presented in Engler and 
Gilg’s “Syllabus der Pflanzenfamilien ” (9th and 10th editions), and the 
arrangement of genera, although generally in accord with the same work, 
has been changed somewhat in the Gramineae and Cruciferae. The order 
used in the Gramineae is taken from Hitchcock’s 11 Genera of Grasses of 
the United States ”(69) which has been widely accepted among students 
of the group. Lack of uniformity in the organization of the difficult group 
of the Cruciferae has led the writer to use that of Gray’s Manual, one of 
the more commonly known texts. So far as possible, the International 
Rules of Botanical Nomenclature have been followed in the selection of 
names, and only those synonyms have been included that will make the 
list usable with standard manuals such as Rydberg’s “ Flora of the Rocky 
Mountains and Adjacent Plains,” Britton and Brown’s “ Illustrated Flora 
of the Northern United States and Canada,” and “ Gray’s New Manual of 
Botany” (7th edition). References to recent treatments of certain species 
or groups of species are given whenever they are available. The writer 
has made no extensive effort to obtain local common names, and those 
given have been selected from the standard manuals because of their wide 
usage in other regions. 
Many persons have been of assistance in the preparation of the list. 
The writer is most indebted to Professor M. L. Fernald of Harvard Uni- 
versity, who has given freely of his time and extensive knowledge of north- 
ern floras. In several groups, such as Potamogeton, Carex, Draba, Erigeron, 
Antennaria, Arnica, and Taraxacum, he has made many of the determina- 
tions of difficult species, and has kindly checked the entire list for nomen- 
clatorial errors. Dr. 0. E. Jennings, of the University of Pittsburgh, has 
lent much encouragement and assistance, particularly in the earlier stages 
of the work. Thanks are due also to Dr, J. H. Schaffner, of Ohio State 
University, who has checked the 1926-27 collections of Equisetum ; to Dr. 
F. W. Pennell, of the Academy of Natural Sciences, Philadelphia, who has 
verified the determinations of the Scrophulariaceae; to the late Mr. K. K. 
