W-EEEEa E

EMARCH 10, 1950

SOIL EROSION BY RAINSTORMSW. D. ELLISON

EDWARD LEE THORNDIKE: 1874-1949ROBERT S. WOODWORTH

TECHNICAL PAPERS

COMMENTS AND COMMUNICATIONS

BOOK REVIEWS

NEWS AND NOTES

COMPLETE TABLE OF CONTENTS ON PAGE 3VOLUME 111, NUMBER 2880

AMERICAN ASSOCIATION FOR THE

ADVANCEMENT OF SCIENCE

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Vol. 111 No. 2880 Friday, March 10, 1950 Lorin J. Muffli

F. A. MX

Table of Contents

Soil Erosion by Rainstorms:W .D. Ellison...... ....................................... ............................ 245

Edward Lee Thorndike: 1874-1949:Robert S. Woodworth

Technical PapersA Light Polarization Analyzer in theCompound Eye of Limulus:Talbot H. Waterman .252

The Combined Action of Penicillin withStreptomycin or Chloromycetin onEnterococci in Vitro: E. Jawetz,.J. B. Gunnison, and V. R. Coleman 254

Cytologic Demonstration of Nucleic Acidsin Tissue Culture:Robert J. Stein and Horace W. Gerarde ............. 256

Synthesis of. 1-C14-L-Ascorbic Acid:.T. J. Burns and C. G. King .257

Sterile Pieces of Chick Embryo as a Mediumfor the Indefinite Axenic Cultivation ofRhabditii bdgqese Dougherty and Nigon, 1949(Nematoda: .RhabditidaeF7llsworth C. Dougherty.............. 258

Mechanism of the Base-catalyzed Conversionof Acylamino Acids to Acylamido Ketones:Richard H. Wiley .9............ 259

The Pleistocene History of the MississippiRiver: William Herbert Hobbs .2RO

Conmnents and CommunicationsA.,

Research Publication: An Addendum;Catching Fishes with the Hand in India;Relation between Time of Treatment andSprouting of Poisoned Trees .263

Book ReviewsMathematical Biophysics; HumanHelminthology: A Manual for Physicians,Sanitarians, and Medical Zoologists.265

Scientific Book Register ... 266

News and Notes. 267

Science, a ..weekly joiirnnl ftil Ied in 1880,. Is publishedeach Friday by the American Association for the Advance-ment of Science at the Business Press, 10 McGovern Aye.,Lancaster, Pa. Editorial and Advertising Offices, 1515 Massa-chusetts Ave., N.W., WVashington 5, D. C. Telephone, Execu-tive .60fi0.:j'.' Cable address, SCIMAG,. Washington, D. C.Entered as second-class matter at the Post Office at Lancaster,Pa., January 13- 1948, under the'Act of March 3, 1879.Acceptance for mailing at the special rate postage providedfor in the Act of February 28, 1925, embodied in Paragraph(d-2) Section 34.40 P.L. & R. of 1948.Manuscripts submitted for publication should be sent to the

Editorial Office, with stamped, self-addressed envelope en-closed for possible return. The AAAS assumes no responsi-bility for the safety of the manuscripts or for the opinionsexpressed by -contributors.Annual subscription, $7.50; single copies, $.25: foreign

postage, outside thee Pan-American Union, $1.00; Canadian

postage, $.50. Remittances and orders for subscriptions andsingle copies should beksenx to the Circulation Department,Science, 1515 Massachusetts Ave., N.WV., Washington 5, D._C.

Membership correspondence for the AAAS should be addressedto the Administrative Secretary'at the same address.

Change of address. tour weeks' notice is required forchange of address. This should be sent to Science Recorder,1515 Massachusetts Ave., N.W., Washington 5, D. C. Whenordering a change, it is necessary to furnish an address stencillabel from a recent issue. Claims for a missing number willnot be allowed if received more than 60 days from date ofissue. No claims allowed from subscribers due to failure tonotify the Circulation Department of a change of address orbecause an issue is missing from 'their files, or for any reasonfrom subscribers in Central Europe, Asia, or the PacificIslands (other than Hawaii).The AAAS also publishes The Scientific Monthly. Subscrip-

tion rates on request.

UAS EDITORIAL BOARDerm# lrpire June 30, 1950)itsell H. Bentley Glass

Karl Lark-Horcwitzins Malcolm H. SoulkHoward A. Meyerhoff

Chairman

Beth WilsonExecutive Editor of Science

loulton, Advertising Representative

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Develops the basic principles on the behavior of plants under natural or controlled conditions.The authors stress the practical application of theoretical principles and have included a wealthof references to the literature on the subject. The illustrations are numerous and well chosen

THE CHEMISTRY AND METALLURGY OF MISCELLANEOUSMATERIALS. Thermodynamics

Edited by LAURENCE L. QUILL, Michigan State College. National Nuclear Energy Series.Plutonium Project Record. Division IV. Volume 19B. 352 pages, $3.00

An important new volume in the National Nuclear Energy Series of special interest to chemists.The papers which make up this book include surveys of the thermodynamic properties of the ele-ments and many compounds, including those of the rare earths.

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Part I of this book discusses the general physical principles underlying the operation of ionizationchambers and counters, with special emphasis on subjects that are of importance in modern detec-tion techniques. Part II contains a detailed discussion of a number of detectors developed by theauthors and others at the Los Alamos Laboratory for the study of different kinds of radiations.

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