982 
acquired since that time, the larger part of the 
first edition having been destroyed by fire in 
the building of the publishers. 
In its broadest conception the subject is 
happily defined as ‘ the study of vegetation,’ or 
in other words, the study of the floral covering 
of any area in the aggregate. It deals with the 
plant groups rather than with individuals, and 
with the interrelations of species rather than 
with the species themselves, and discusses the 
reasons why certain plants have become estab- 
lished in certain areas, the effects of environ- 
ment, ete. 
The treatment of the subject begins with an 
historical review of the investigations which 
have been made in the flora of Nebraska, com- 
mencing with the expedition of Lewis and 
Clarke during the years 1803-1806, and con- 
tinues through what may be called the era of 
exploration, to about 1870, up to which time 
the study of botany was merely incidental, in 
connection with general surveys and explora- 
tions. Botany as a distinct subject of investi- 
gation did not receive attention until 1871, and 
it was not until 1884 that it was prosecuted in 
earnest, under the direction of Dr. C. E. Bes- 
sey, who was elected to the then newly created 
chair of botany in the University of Nebraska. 
The botanical seminar of the University was 
organized, and for the first time a systematic 
investigation of the flora of the State was begun. 
The preliminary work. of cataloging the flora 
of the state was accomplished and then was 
commenced the study of the vegetation as a 
whole, in connection with topography, geology, 
meteorology, etc. 
Four phytogeographical ‘regions’ are recog- 
nized, as follows : 
I. Wooded-bluff and Meadow-land. 
Il. Prairie. 
III. Sandhill. 
IV. Foothill. 
Regional limits, within a relatively small and 
artifically limited area such as the State of Ne- 
braska, are primarily dependent upon physiog- 
raphy. Vegetation ‘zones’ and ‘realms’ are 
only applicable to more extended areas, with 
natural boundaries based on geographic or 
climatic conditions. 
Following the system of Drude, the phyto- 
SCIENCE. 
(N.S. Vou. XIII. No. 338. 
geographic regions of Nebraska would all be 
included within the Middle North American 
Realm of the Northern Zone, and by a division of 
this realm into ‘ provinces’ (Allegheny, Prairie, 
Rocky Mountain, Great Basin and California) 
the greater portion of the State would fall 
within the second of these, with a small strip 
along the eastern edge representing the first. 
Lists of species peculiar to each region, those 
that are common to two of the regions, and 
those that are common to three or more of the 
regions, are given. The distribution of any 
species, or in other words the area over which 
it occurs, is of course a mere matter of more or 
less careful observation, but the abundance of 
a species can only be determined by careful in- 
_vestigation and calculation, the method of 
which is described, together with the formule 
adopted. 
The terms employed are somewhat bewilder- 
ing in their number and the fineness of their 
distinctions, and doubtless many who are not 
directly interested in the subject may become 
impatient at the necessity for mastering the 
differences between ‘abundant,’ ‘ frequent,’ 
“sub-frequent,’ ‘infrequent,’ ‘sparse,’ ‘rare,’ 
‘solitary,’ ‘copious,’ ‘gregarious,’ ‘ gregario- 
copious,’ ete. 
In the division of the plants into ‘ vegetation- 
forms’ will be found another series of terms, 
popular and scientific, such as woody plants 
(‘ trees,’ ‘shrubs,’ ‘under-shrubs,’ ‘climbers 
and twiners’), half. shrubs, herbs (‘rosettes,’ 
‘mats,’ ‘succulents,’ ‘sod-formers,’ ‘ rootstock- 
plants,’ etc.), water plants (‘ floating,’ ‘sub- 
merged’ and ‘amphibian ’), saprophytes, para- 
sites, mosses, fungi, algze, etc., with discussion 
of habitat, foliage, protective devices, period 
of flowering, methods of dissemination, ete. 
The factors concerned in the phenomena of 
phyto-geography are both physical and biolog- 
ical. They are connected with environment 
(topography, temperature, moisture, mechan- 
ical and chemical composition of the soil, etc.), 
and with the influence of animals, including 
man, as well as with the influence of plants 
upon each other, and each natural group of 
plants may be affected differently by the same 
factor or factors. In this connection each 
natural group is discussed in sequence. 
