May 10, 1901.] 
or aggraded to a nearly even surface. The 
crescentic sand-dune is taken as a normal form 
on an open surface. The necessity of a former 
pluvial period to explain the wadies of deserts, 
as stated by some writers, is doubted; and in 
spite of the violence of occasional cloud-burst 
floods, the chief agency in the preparation of 
desert topography is held to be the wind; a 
conclusion that seems to have been long famil- 
iar to the Bedouin, just as the transportation of 
erratics by a former extension of glaciers has 
long been known to Swiss peasants. The im- 
portance of identifying ancient desert forma- 
tions in the geological series is emphasized. 
Although peneplanation under arid condi- 
tions is not excluded from the Walther dis- 
cussion, the systematic advance of the processes 
of arid denudation through an ideal cycle and 
the description of the forms thus successively 
developed are not fully presented. Old and 
young deserts are not clearly separated. In 
some arid regions, the marginal deposits of the 
coarse waste rise upon the flanks of the enclos- 
ing mountains; in others a piedmont slope of 
evenly. degraded rock, veneered with thin 
sheets of waste, slopes gently forward from the 
mountain base. The first is probably a younger 
form than the second; but no one has yet 
studied out the full series of still younger and 
still older forms of an arid landscape. 
W. M. Davis. 
THE AMERICAN GEOGRAPHICAL SOCIETY. 
THE American Geographical Society will 
move into its new building in 81st Street, New 
York, in the course of the next two or three 
months. The Society has at present about 
1,200 members and, to still further increase its 
numbers, has sent out a circular, from which 
we quote the following : 
The objects of the American Geographical Society 
are: The.collection, discussion and diffusion of geo- 
graphical information ; the promotion of the explora- 
tion. of our territory and of the survey and preserva- 
tion of our harbors; the establishment in the chief 
maritime city of the Union of a place where will be 
afforded the means of obtaining accurate information 
of every part of the globe, and the registration and 
careful record of discoveries and studies in geography 
and the related sciences. 
SCIENCE. 
703 
The Society was founded in 1852. One of but 
twelve similar societies at that time, it now exchanges 
its publications with three hundred scientific asso- 
ciations scattered throughout the world. 
The Society has outgrown the house, No. 11 West 
Twenty-ninth Street, in which it has been lodged for 
more than twenty years. A handsome fireproof 
building is now being erected in West Eighty-first 
Street, opposite Manhattan Square. This will afford 
perfect security to the library of 30,000 volumes— 
one of the foremost geographical libraries of the world 
—the thousands of maps and charts and the collection 
of atlases of the sixteenth, seventeenth and eighteenth 
centuries, now in the map rooms, and will also pro- 
vide ample accommodation for readers and students. 
Travelers, men of science, and others properly ac- 
credited, are welcomed at the rooms of the Society and 
freely offered the use of the library and collections, 
The Society is now free from debt and possesses a 
property which has of late been steadily growing in 
value. 
It is desired to add to the number of fellows on 
the roll in order to strengthen and extend the influ- 
ence and the usefulness of the Society. 
No special qualification for fellowship is required 
other than interest in the spread of knowledge and 
the advancement of science. Theannual dues are $10. 
RESOLUTION OF THE COMMITTEE OF CEN- 
TRAL NATURALISTS. 
AT a meeting of the committee appointed by 
the Chicago meeting of naturalists to arrange 
for the next meeting, held at Chicago, March 
28th, the following was voted. The vote has 
since been submitted to a number of the older 
members of the American Society of Natural- 
ists living in the Central States and has been 
approved by them. It may, therefore, be taken 
to represent the prevailing sense of the natu- 
ralists of the Central States. 
VoreD: Whereas, the naturalists of the 
Central States propose to meet annually at some 
convenient point for intercourse and the read- 
ing of papers ; 
And whereas, no point east of the Alleghenies 
(to which territory the meetings of the Amer- 
ican Society of Naturalists are by its constitu- 
tion confined) is practicable as such meeting 
point ; 
And whereas, the central naturalists would 
view with approval the formation of a national 
body which might properly be called the Amer- 
