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Vol. 108 No. 2796RESEARCH DEPARTMENTFABRICATING DIVISION

PERMANENTE METALS CORP.

Friday, July 30, 1948

The Chromosomes and Relationshipsof Metasequoia and Sequoia:G. L. Stebbins, Jr. .. ....... 95

Association AffairsCentennialCelebration Notes ................................... 99

News and Notes. loo

Comments and Communications. 107

Technical PapersPhotosynthetic Studies With Mutant Strains

of Chlorella:Edwin A. Davis ............... ........................ 110

Fractionation of Amino Acids From Hydroly-sates in Nonaqueous Systems:E. V. McCollum and Agatha A. Rider ............... 111

The Control of Grass Weeds in Sugar-CaneFields in Puerto Rico:

J.A. B. Nolla ............. .......................... 112

Demonstration of Reducing Enzyme Systemsin Neoplasms and Living Mammalian Tissuesby Triphenyltetrazolium Chloride:Francis H. Straus, Nicholas D. Cheronis,and Elizabeth Straus ..... ............ 113

Palynological Studies at Sodon Lake: I. Size-Frequency Study of Fossil Spruce Pollen:

StanleyA. .........................................................................

Inhibition of Glycolysis in Vitro by ImpurePenicillin: Ernest Kun ...... ........... 117

In the LaboratoryBenzene-Ether Extracted Rabies Vaccine:John T. Wright, J. Frederick Bell, andKarl Habel .................... 118

A Constant-Temperature MicromanipulationChamber: Kenneth M. Richter ....................... 119

The Use of Thionyl Chloride in the Prepara-tion of Schiff's Reagent: James D. Bargerand Edward D. DeLamater ............... ........ 121

Plant Virus for Electron Microscopy:James Johnson ........... . 122

Science, a weekly journal, Is published each Friday by theAmerican Association for the Advancement of Science atThe Business Press, Incorporated, N. Queen St. and McGovernAve., Lancaster, Pa. Founded in 1880, it has been since1900 the official publication of the AAAS. Editorial and Ad-vertising Offices, 1515 Massachusetts Avenue. N.W.. Wash-ington 5, D. C. Telephone, EXecutive 60 or 6061. Cableaddress, SCIMAG, Washington. D. C. Entered as second-class matter at the Post Off0ce at Lancaster, Pa.. January 13,198 under the Act of March 3, 1879. Acceptance for mail-ing at the special rate postage provided for in the Act ofFebruary 28, 1925, embodied in paragraph 4, Bec. 538. P. L.and R., authorized January 13, 1948.

Articles offered for publication should be sent to the Edi-tor. The AAAS assumes no responsibility for the opinionsexpressed by contributors. Membership correspondence forthe S should be sent to the Administrative Secretary.Annual subscription, $7.50; single copies, $.25; foreign

postage (outside the Pan-American Union). $1.00 extra;

2

Canadian postage, $.50 extra. Remittances and orders forsubscription and single copies should be sent to the Circula-tion Department, AAAS, North Queen Street and McGovernAvenue, Lancaster Pennsylvania, and 1515 MassachusettsAvenue N.W., Wasihington 5, D. C. Claims for missing num-bers will not be allowed if received more than 60 days fromdate of issue. No claims allowed from subscribers in CentralEurope, Asia, or the Pacific Islands other than Hawaii or be-cause of failure to notify the Circulation Department of achange of address or because copy is missing from the files.Change of address. Four weeks notice is required for

change of address. This should be sent to Sosence. 1515Massachusetts Avenue, N.W., Washington 5, D. C. Whenordering a change, please furnish an address stencil labelfrom a recent issue. Address changes can be made only Ifthe old as well as the new address is supplied.The American Association for the Advancement of Science

also publishes The Scientsfl Monthly. Subscription rateson request.

Mildred Atwood F. A. Moulton

Acting Editor Advertising Manager

Publications CommitteeFarrington Danies, John E. Flynn, ~irtey F.

Mather, Walter B. Milcs, Malcolm H. Soule.Steven M. Spencer

CONTENTS

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(1) Ref: Porter, Durrell & Romm, Plant Physiol. 22, 149 (1947);Mattson, Jensen and Dutcher, Science 106, 294 (1947); Lakon,Ber. dtsch. chem. Ges. 60, 299, 434 (1942).

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Register Now

for A.A.A.S.

WHAT, WHEN, WHERE, and HOW TO GETTHERE:-questions about sessions of the Centennial Meeting inWashington, September 13-17, will be answered completely in the

1848-1948 General Program. To be sure of having the answers in advance, so

that you may plan which sessions to attend and otherwise make themost of your time in Washington, register now for the meeting in

aAn ~~~~September.The General Program and informative publications about Washington will be mailed to

advance registrants in mid-August. The Program will list the speakers, the titles of theirpapers and the location of each session and special event. In addition, it will contain in-formation about hotels, transportation, eating facilities, messenger service, lost and foundarrangements, and points of interest to the historically-minded as well as to those interested inscientific research and its administration in the nation 'I capital. Moreover, the GeneralProgram will be a treasured memento of one of the outstanding events in the history oforganized science in America.

In order that you may plan in advance your schedule of activities during the CentennialCelebration, please fill in the registration blank below and send it, together with your checkor money order for the correct fee, to the A.A.A.S. Administrative Offices, 1515 Massachu-setts Avenue, N.W., Washington 5, D. C. (Your convention address may be filled in later.)This information will be placed on file in the Visible Directory to be located in the StatlerHotel during the meetings, where it will be easily accessible for quick inspection. Findingyour friends and having them find you will be no problem if you and they have registered.For your convenience addresses of friends may be obtained by calling EX. 1000 and askingfor the A.A.A.S. Visible Directory.

If you are planning to participate in the Centenary, don't fail toregister now

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AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCEREGISTRATION BLANK

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1. Registration Fee $2.00 A.A.A.S. Member Check$3.00 Nonmember 0 One

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This Directory Card will help your friends locate you. Please type or print clearly In ink.

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______INTERSCIENCE_____RADIOACTIVE INDICATORS

Their Application in Biochemistry, Animal Physiology, and PathologyBy George HEVESY

Institute for Research in Organic Chemistry, University ofStockholm, Sweden; Institute for Theoretical Physics,

University of Copenhagen,-Denmark1948 approx. 572 pages 97 illus., 192 tables approx. $9.00

IADVANCES IN PEDIATRICSVolume 3

Edited by S. Z. LEVINE, Allan M. BUTLER,L. Emmett HOLT, Jr., A. Ashley WEECH

Contributors: Clement A. Smith, T. L. Terry (deceased), Milton J. E. Senn, WilliamG. Lennox, Joseph Stokes, Jr., Lawson Wilkins, Hilde Bruch, Beckett Howorth

1948 6x9 373 pages 77 illus. $7.50 a

QUANTUM THEORY OF FIELDSBy Gregor WENTZEL, University of Zurich

Translated from the German1948 6x9 approx. 220 pages approx. $5.00

ENCYCLOPEDIAOF CHEMICAL TECHNOLOGY

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Polytechnic Institute of BrooklynAssistant Editors: Janet D. Scott and Anthony Standen

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