O64 
order of the elements must be preserved 
though the manner of their association may 
be indifferent, and a power of a binomial is 
then different from a product. This ap- 
plies whether the sum or product occurs 
simply or as the index of a base. 
Descartes wedded algebra to geometry ; 
formalism tends to divorce them. The prog- 
ress of mathematics within the century 
has been from formalism towards realism ; 
and in the coming century, it may be pre- 
dicted, symbolism will more and more give 
place to notation, conventions to principles 
and loose extensions to rigorous generaliza- 
tions. 
ALEXANDER MACFARLANE. 
LEHIGH UNIVERSITY. 
PROCEEDINGS OF THE BOTANICAL CLUB OF 
THE AMERICAN ASSOCIATION FOR THE 
ADVANCEMENT OF SCIENCE AT CO- 
LUMBUS, AUGUST 21-24, 1899. 
Tuer Botanical Club met in the room as- 
signed for the meetings of Section G pursu- 
ant to the resolution adopted by the Boston 
meeting, Tuesday morning at 9 o’clock, Dr. 
Byron D. Halsted presiding. The sessions 
were continued at that hour each morning, 
and completed by a meeting at 1:30 p. m., 
Thursday. In the absence of the Secre- 
tary, A. D. Selby was chosen Secretary pro 
tempore. 
The attendance and interest in the pro- 
ceedings of the Club were very satisfactory. 
The number of papers read was quite equal 
to the time secured for them. 
Under the title ‘ A Greasewood Compass 
Plant,’ Dr. C. E. Bessey reported that on 
the high, western Nebraska foot-hills a 
shrubby species of Sarcobatus was observed 
to bear its leaves in an upright position, 
with their blades parallel to the meridian. 
Specimens were obtained for microscopic ex- 
amination. 
The same author gave an account of ‘A 
Visit to the Original Station of the Rydberg 
SCIENCE. 
[N. S. Vou. X. No. 246. 
Cottonwood.’ ‘This species (Populus acu- 
minata Ryd.) was discovered a few years 
ago in Roubedean Township, in Scott’s Bluff 
County, in western Nebraska, in Carter 
Cafion. This is a broad cafion bounded by 
high pine-covered buttes, and in the bottom 
of the broad cafion is a narrower one fringed 
with deciduous trees—box elder, elm, cot- 
tonwood, willow, plum, red cedar, ete., and 
among them are clumps of the Rydberg 
cottonwood. The trees are symmetrical 
and of much greater beauty than those of 
the common cottonwood. When old the 
bark of the trunk is light-colored and very 
deeply fissured. 
Dr. N. L. Britton reported to the Club 
that Mr. and Mrs. A. A. Heller, who were 
sent to Porto Rico last winter as collectors 
for the New York Botanical Garden, had 
returned, having secured about 1,400 num- 
bers, representing probably over 1,200 spe- 
cies, and over 6,000 specimens of plants. 
They are now being studied. 
Dr. William Saunders gave a brief ac- 
count of ‘The Arboretum and Botanic Gar- 
den of the Central Experimental Farm at 
Ottawa, Canada, established in 1889.’ Dur- 
ing that year 200 species and varieties of 
woody plants were planted in botanical 
groups. Additions were made from year to 
year, and by the end of 1894 the collection 
included about 600 different species and 
varieties. Since 1894 progress has been 
much more rapid, and up to the present 
time the total number of species under test 
or which have been tested is 3,071—of these 
1,465 have been found hardy, 320 half 
hardy, 229 tender, 307 winter-killed and 
740 have not been tested long enough 
to admit of an opinion on their hardiness. 
Where specimens pass the winter unin- 
jured, or with very small injury to the tips 
of the branches only, they are classed as 
hardy. When killed back one-fourth to 
one-half, half-hardy ; when killed to the 
snow-line, tender. A considerable collec- 
