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We have been handling Natural History Material of all kinds for the past fifty years, and so have accumulated a very complete stock. Our prices are as low as the quality of the specimens will permit. We are constantly preparing circulars and price lists covering our material in the different branches, which we will be pleased to send free of charge to the readers of Science. SOME OF OUR RECENT CIRCULARS: S-121 Rare Bird Skins S-122 Mounted Bird Skins S-98 Material for Dissection S-123 Philippine Land Shells S-120 Special Minerals 5-110 Complete Trilobites S-111 Jurassic Fossils S-119 Cretaceous Fossils CONCHOLOGY

GEOLOGY

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Georgetown University

SCHOOL OF MEDICINE AND

DENTAL DEPARTMENT

The Sixty-fourth Session began in September and con tinues eight and one-half months. Six-Year Collegiate and Medi. cal Course leading to degrees B.S. and M.D. Practical laboratory work under special instructors, in Anatomy, Physiology, Chem istry, Histology, Pathology and Bacteriology. Ample facilities for clinical experience and practical work in hospitals of city and in the University Hospital, containing in all over 3,000 beds. For particulars address

GEORGE M. KOBER, M. D.
Dean School of Medicine, 1819 Q Street
SHIRLEY W. BOWLES, D.D.S.
Dean Dental Department, 1616 I Street, N. W.
Washington, D. C

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Edited by James W. Glover, Ph. D., Professor of Mathematics and Insurance. University of Michigan. 620 pages, 6 x 9". Cloth, $3.90 postpaid.

Combines in one book all tables required by collegestudents in mathematics of finance, insurance, statistics.. Important new tables for actuaries, statisticians, biometri.. cians. Logarithms and values of compound interest func-. tions and conversion factors; life insurance, disability insurance, joint life, United States life tables; areas, ordinates, second to eighth derivatives of normal curve of error, extensive tables for exponential growth curve. Seven place logarithms from 1 to 100,000.

functions.

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Bausch & Lomb Optical Co.,
438 St. Paul St., Rochester, N. Y.
Leading American Makers of Pho-
tographic Lenses, Stereo-Prism Bin-
oculars, Telescopes, Magnifiers, Mi-
Projection Apparatus
croscopes,
Automobile Lenses
(Balopticons),
Grade Optical

Products.

that eyes may see

better and farther.

(British Made)

STUDENTS' MICROSCOPES

The "Praxis" Stand is the Student's model par excellence. Made throughout with the same ac

curacy and

as

finish on Watson's

highest priced Stands.

A few special points are:- - Standardization so that additional movements I may be fitted as required. Lever fine adjustment. Constructed of two solid castings and indestructible.

All

parts are slotted and sprung to compen sate for wear.

Catalogue of Microscopes and accessories for all purposes gratis on request from

W. WATSON & SONS, Ltd.
Established 1837

313, High Holborn, London, England

Naturalists' Supplies

We carry stock for prompt delivery

Collecting Utensils.

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Breeding Apparatus and Cages for Living Animals.
Preparing and Preserving Utensils.

IV.

V.

VI.

Cabinets, Insect Cases and Lining Material.
Magnifiers, Microscopes and Accessories.

Botanists Supplies.

VII. Explorers' and Collectors' Camp Outfits.
Miscellaneous Naturalists' Supplies.

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K-S Museum Cabinets of Glass and Metal

New Illustrated Biological Catalog will be sent free of charge upon application

THE KNY-SCHEERER CORPORATION

Department of Natural Science

G. Lagai, Ph.D.

404-410 WEST 27TH STREET, NEW YORK CITY, N. Y.

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Our Subscribers Include:

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J'

UST as America leads the world in recon-
struction,wealth,invention, manufacture, so
The AMERICANA establishes a new lead-
ership over all reference works.

The revolutions in thought and progress, brought
about by the War, made all encyclopedias
obsolete. A restatement of the World's knowledge
thus became imperative. The AMERICANA
gives a wide view of the world as it is today
not as it was ten years ago.

COPYRIGHTED

1920

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ENCYCLOPEDIA AMERICANA

CORPORATION

27 WILLIAM ST., NEW YORK PEOPLE'S GAS BLDG., CHICAGO
Gentlemen:

NAME
ADDRESS

Please send descriptive literature - AMERICANA

The Boston
Public

Library says:

"This is the first edition of any one of the larg er encyclopedias to be published since the close of the European War."

from

NEWS NOTES

OF THE

BOSTON

PUBLIC

LIBRARY

January

15th 1921

THE SCIENTIFIC

MONTHLY

OCTOBER, 1922

THE CONSERVATION AND PROPER UTILIZATION OF OUR NATURAL RESOURCES'

By Dr. BARTON WARREN EVERMANN

DIRECTOR OF THE MUSEUM OF THE CALIFORNIA ACADEMY OF SCIENCES

THERM

HE natural resources of the United States are the richest and most varied of any country in the world. It is only necessary to call attention to our great coal and oil fields and natural gas, our varied mineral resources, wonderful forests of hard and soft woods, our multitude of species of wild game mammals and birds and fur-bearing animals, the hundreds of species of useful insectivorous and predaceous birds, and the rich fisheries of our Atlantic, Gulf and Pacific coasts, Great Lakes and other interior waters, to enable us to realize that our country has been exceedingly blessed in this regard.

And this very richness of natural resources has had much to do with making us the most short-sighted, the most extravagant and the most wasteful people in all the world. There is not one of our natural resources which, in the beginning of the development of the country, was not handled in very wasteful ways; in numerous instances so wasteful and destructive that the resource was wiped out almost, if not quite, entirely. Such were the Buffalo, Wild Pigeon, Atlantic Salmon, Wild Turkey, Gray Squirrel, Sturgeon, Sea Otter, natural gas, white pine and many others that might be mentioned.

It is now too late to do anything to correct the mistakes with some of the species that were once valuable assets to our people, because they are now entirely extinct, or are species whose wellbeing depends upon an environment which has passed and can not be restored. But there are many species of the native flora and fauna with which it is not too late and which, with proper care,

1 Presidential address delivered June 22, 1922, at the Salt Lake City meeting of the American Association for the Advancement of Science.

Vol. XV.-19.

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