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FATIGUE AND IMPAIRMENT IN MANBy S. HOWARD BARTLEY and ELOISU CHUTI, Dartmouth Eye Institute, PIartmouth Medical School. Inpress-ready for fall classes

The authors combine a review of the many types of con- tion (impairment). The book develops the thesis thatventional fatigue studies and a presentation of a new fatigue pertains to organization rather than to energyviewpoint which distinguishes between the personal expenditure, and arises from frustration; not directlyphenomenon (fatigue) and phenomena of tissue modifica- from activity.

INTRODUCTION TO PALEOBOTANYBy CHESTER A. ARNOLD, University of Michigan. Mcrlraw-lrill Publications in the Botanical Sciences.In press-ready for fall classes.

In this new book the author meets the longfelt need for between living and extinct plants are stressed, and in-an up-to-date, comprehensive textbook on paleobotany. formation recently acquired through use of new tech-The text is organized around the large plant groups and niques is presented.includes numerous original illustrations. Relationships

DISEASES OF FIELD CROPSBy JAMES G. DICKSON, University of Wisconsin. McGraw-Hill Publications in the Agricultural Sciences.411 pages, $4.50.

This volume represents a complete revision and expan- torical and current information on the diseases of thesion of the author's privately printed Oulline of Diseases more important field crop plants. Emphasis is placedof Cereal and Forage Crop Plants of the Northern Part of on the symptoms of the diseases, the causal factors, andthe U.S. The present book combines the pertinent his- disease control.

H ISTOR I CAL GEOLOGY. New second editionBy RUSSELL C. HUSSEY, University of Michigan.. In press-ready for fall classes.

As in the previous edition, the author presents a lucid events, rather than a mass of details. The new editionand well-organized text covering the geologic history of covers recent developments and includes new illustra-North America and inhabitants throughout two billion tions of exceptional quality and interest.years, with emphasis on broad panoramas of important

ANIMAL ANATOMY AND PSYCHOLOGYWritten and illustrated by CHARLES R. KNIGHT. 149 pages, $5.00

A master of the art of animal portraiture, Charles R. 123 magnificent illustrations represent faithfully theKnight has compiled the most complete book available living animal in many physical poses and psychologicalon the anatomy and psychology involved in the drawing expressions. Special attention is given to the jointsof animals, both vertebrates and invertebrates. The of the animal and how they function in various positions.

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Just PublishedChemistry of Muscular Contraction

by A. SZENT.GYORGYI, University, Budapest1947, viii + 149 pages, illustrated $4.50

Professor A. Szent-Gyorgyi is well-known for his isolation and identification ofVitamin CQ. For the discovery of Vitamin PI he was awarded the Nobel Prize in Medi-cine in 1937. During the war he and his school entered a new field of investigation andproduced research on the chemistry of muscles, which appears likely to revolutionizenot only our conceptions about muscle, but many other aspects of biochemistry.

Radioactive Tracers in BiologyAn Introduction to Tracer Methodology

by MARTIN D. KAMEN, Washington University, St. Louis, Missouri1947, xi + 281 pages, illustrated $5.80

The publication of this volume marks the initial appearance of a text devotedprimarily to biological applications of radioactive tracer isotopes. The need for such atext is emphasized by recent spectacular success in expansion of radioactive isotopeproduction brought about by the development of atomic energy.

Biochemistry of Cancerby JESSE P. GREENSTEIN, National Cancer Institute, Bethesda, Maryland1947, viii + 389 pages, illustrated $7.80

This volume is an integration of the results of modern experimental approachesalong biological and biochemical lines to the study of cancer. It is intended to beinformative, not only to the professional cancer investigator, but to biologists and bio-chemists in all fields of endeavor, as well as to physicians and medical students.

Advances in GeneticsEdited by M. DEMEREC, Carnegie Institution, Cold Spring Harbor, New YorkVolume I, 1947, xvi + 458 pages, illustrated $7.50

This new series will present critical summaries of various genetic problems writtenby competent geneticists. One volume will be published yearly.

Contributors: S. S. ATWOOD, E. B. BABCOCK, M. GORDON, M. R. IRWIN, J. L. Lua,P. C. MANGELSDORF, R. R. SHRODE, T. M. SONNEBORN, W. P. SPENCER, G. L. STEBBINS,JR. AND S. G. STEPHENS.

ACADEMIC PRESS INC., PUBLISHERS125 East 23rd Street New York 10, New York

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Mavor:GENERALBIOLOGY

Third Edition

Written in a clear simple style and main-taining a logical arrangement of material,the new edition of this widely popular texthas been revised throughout and much new

material added. New chapters have beenincluded to give a background for the chem-istry and physics of the cell. The materialon hormones and vitamins has been broughtup to date; the treatment of metabolism hasbeen shifted to a new chapter "Food Mate-rials and Metabolism"; and the chapterson the Mechanism of Evolution and EarlyMan have been largely rewritten. The textmakes possible different treatments of sub-ject matter and is designed for a year'scourse. To be published in the summer.

*5.50 (probable)

LABORATORY EXERCISESIN GENERAL BIOLOGY

Third Edition

Designed to accompany the new edition ofGENERAL BIOLOGY, this book providesa wide range of subjects and considerablechoice in the selection of laboratory mate-rial. Time-saving devices both for theinstructor and for the student are employed.Sample schedules. for year courses havingone and two laboratory periods per week are

given. Work sheets are included. To bepublished in the summer. $3.25 (probable)

A set of five film strips of approximatelyfifty frames each will be available to accom-pany the Third Edition of Mavor: GENE-RAL BIOLOGY. Summer, 1947. Prob-able price *15.00 a set. Order from CollegeDepartment.

Gates:HUMANGENETICS

This comprehensive and authoritative workapproaches the subject from a broad bio-logical point of view, and makes use ofembryology, morphology, physiology, bio-chemistry, and anthropology in explainingthe development and inheritance of bothnormal and abnormal conditions. Through-out the chapters in which various physicaland physiological abnormalities are consid-ered, experiments, especially with mam-

mals, are referred to whenever they throwlight on any problem of human genetics.The work includes a large selected list ofreferences and a full index. 1518 pages

Two-volume Set *15.00

Stiles:TRACE ELEMENTSIN PLANTS ANDAN IMALS

An authoritative account of the part playedby chemical or trace elements in plants andanimals, this book summarizes the informa-tion available at the present time on theeffects of those chemical elements which are

essential to the lives of plants and animals,but which are required in extremely smallquantities. It provides a digest in con-

venient form of all the available materialon the subject. The author carefully sum-

marizes the recent theories and discoveries,describes experiments now being carriedout, and points out clearly the present ex-

tent of knowledge in this field. 189 pages*L.75

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M E T H O D S OF VITAMIN A S S A YPrepared and Edited by

ASSOCIATION OF VITAMIN CHEMISTS, INC.Chicago, llinois

1947 6x9 £08 pages 10 illutrations

i. Sampling of Foods for VitaminAnalysis

The General ProblemSampling of Various Types of

ProductsMeats-Vegetables and Fruits-Cereals-Pharmaceuticals-Blood and Urine

2.. Vitamin AColorimetric MethodUltraviolet Absorption MethodApplication of Methods

3. CaroteneChromatographic MethodSolvent Partition MethodApplication. of Methods

4. ThiamineThiochrome Method

5. RiboflavinFluorometric MethodMicrobiological MethodApplication of Methods

6. NiacinMicrobiological MethodApplication of Methods

7. Ascorbic Acid2,6-DichlorophenolindophenolVisual Titration Method

Photometric Method2.,4-Dinitrophenylhydrazine MethodApplication of Methods

8. Other Vitamin MethodsVitamins D, E, and K-PantothenicAcid-Pyridoxine-Biotin-Folic Acid-p-Aminobenzoic Acid-Inositol-Choline

9. Use of Check Samples in Control ofVitamin Methods

Index

PHYSIOLOGY OF MAN IN THE DESERTBy E. F. ADOLPH and ASSOCIATES

Department ofPhyuo, The Univeriy of Rochest

1947 6x9 370 pages 185 illustrations app. $6.00

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Personnel Placement

POSITIONS WANTED

The Clifoi Medical Bureau. Agency for sciustific and lay personnel inmedicine, biology, chemistry, physics and allied sciences, supplies teachers,research workers, laboratory dieners, skilled office help. Prompt service.Registration free. Your patronage respectfully solicited. Mmx CAm.ORNA MEcDIAL BuixAU, Agency, Arcade Medical Center, 696 Colorado

Street, Pasadena 1, California.

Biologist, MS, MA, 18 years successful college teaching: com arativeanatomy, histology, genetics, microtechnique, bacteriology, biology.Primary interest teaching. Box 903, SCIENCE.

Personnel PlacementAttractive industrial research, production and sales positions for agrono-mists; bacteriologists: chemists. analytical, biological, inorganic, organic,pharmaceutical, physical; chemical engineers; entomologists; geologists;horticulturists; metallurgists; microscopists; pharmacologists; physiciansand surgeons; physicists; plant pathologists and physiologists. ChemicalDepartment, Position Securing Bureau, Inc. (Agency) 45 John Street,New York City.

Fully accredited endowed college, Ohio, would like to hear from personsinterested in either of the following positions as assistant or associate pro-fessor: (1) assume full charge of physical science survey course; (2) teachsome combination of general, analytical, or physical chemistry. Box 909,SCIENCE.

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Medical Mycologist available for research laboratory, hospital or teaching Micro-analyst: Medical research institute in New York has opening for anposition. Box 910, SCIENCE. organic micro-analyst with experience. State educational record experi-

ence, age, present salary, and salary desired. Box 911, SCIENCE.PhD Parasitologist, Protozoologist: Long research experience in chemo-therapyand diagnostic techniques desires position either in medical schoolor industrial laboratory. Box 908, SCIENCE.

Parasitologist: MA (Bacteriology), PhD (Bacteriology and Parasitology):several years science teacher in the public schools; three years assistant de-partment of pathology, university medical school; six years assistant pro-lessor, directing own work in parasitology; for further information, pleasewrite M. Burneice Larson, Director, The Medical Bureau, Palmolive Build-ing, Chicago 11.

Physicist, PhD; ionic, nuclear physics background; university teachingexperience; mass spectrometer, X-ray diffraction industrial experience;desires academic position primarily. Recently with National GeographicEclipse Expedition. Immediately available. Box 904, SCIENCE.

Zoologist, Ph.D. in August. Chief interest vertebrates, ecology, physiol-ogy. Some teaching experience. Desires position with time for research.Box 184, SCz POcx.

POSITIONS OPEN

Positions Open: (a) Endocrinologist to develop new department; manu-facturing production experience desirable; duties consist of supervisingmanufacturing of glandular extracts to develop new by-products; $5000-8000. (b) Professor or associate professor in pharmaceutical chemistry andalso associate professor in pharmacognosy; men with backgrounds in phar-macy preferred; school of pharmacy, state university; salary $5100 and $4500respectively. (c) Associate scientist for investigation dealing with use ofradioactive isotopes in biochemistry; PhD in biochemistry required; uni-versity appointment. (d) Instructors for department of biology of westernuniversity; should be qualified to teach general biology, bacteriology, com-parative anatomy; candidates with Masters or PhD degrees required; salarydependent upon qualifications. S6-4 Medical Bureau (Burneice Larson,Director), Palmolive Building, Chicago 11.

Man or woman interested in research in experimental pharmacology andtoxicology; PhD in physiology, biochemistry, zoology or a related field;eastern university; permanent; 84000-6000; all replies will be acknowledged.Box 891, SCIENCE.

Chemist-Endocrinologist: Man with experience in liver, pituitaries, andother glandular products, to supervise manufacture and sale of productsto pharmaceutical houses. Splendid opportunity for man with vision andinitiative. Mid-west location. Box 912, SCIENCE.

Assistant chief bacteriologist, Ph.D. with major in bacteriology and minorin Chemistry. Position to direct bacteriological research group on vac-cines, antibiotics and new chemotherapeutic agents of well-establishedmidwest pharmaceutical company near large city. Some training or ex-perience in immunology; serology, antibiotics, animal experimentation isdesirable. Salary commensurate with training or experience. Box 913,SCIENCE.

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SUPPLIES AND EQUIPMENT

Cytochrome C and adenosinetriphosphate available for experimental pur-poses. Inquiries are invited for these and other special biochemicalpreparations. Box 889, SCIENCE.

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HELP WANTEDSENIOR METALLURGIST-PhD. or equivalent, to organize andsupervise research program in high temperature materials.

SENIORPHYSICALMETALLURGIST-PhD or equivalent for re-search in X-ray diffraction studies of materials at elevated tempera-tures.

NUCLEAR CHEMIST-PhD or equivalent for nuclear and radio-chemical studies.

SPECTROSCOPER-PhD or equivalent for research and manage-ment of spectographic service laboratory within research division.

CHEMIST AND METALLURGIST-With knowledge of ceramics,to prepare reports and abstracts current literature in research divi-sion. Knowledge of German preferred but not essential.

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The Mlarket PlaceBOOKS

Wanted to purchase-Scientific Periodicals, sets and runs. Foreign-Domestic. Entire Libraries and smaller collections. WALTER J. JOHNSON,125 East 23rd Street, New York 10.

Journals, Periodicals, set and runs. Also whole collections purchased forcash. J. S. CANNER & COMPANY, 909 Boylston Street, Boston 15,Massachusetts.

SUPPLIES AND EQUIPMENTAvailable-Tropic acid, 6 n-propylthiouracil, 5, 6-diaminouracil, pyrimidinederivatives, Equipped laboratory, PhD, will synthesize special organicsBox 907, SCIENCE.

Natural Amino Acids available 1(+) Alanine, 1(+) Glutamine. (1-)

Hydroxyproline, 1(-) Methionine, 1(-) Phenylaline, 1(-) Proline, 1(-)Serine Write for list A4. Bois Laboratories; 607 West 43rd Street, NewYork 18, N. Y.

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SCIENCE1515 Massachusetts Avenue, N. W.

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PHYSICS FOR STUDENTS OFSCIENCE AND ENGINEERING

By WILLIAM H. MICHENER, Assist-ant Professor of Physics, Carnegie In-stitute of Technology.

A general physics textbook designed forstudents of engineering and science. Thesubject matter is well-selected; the presenta-tion clear and pedagogically sound. There isa minimum of derived formulas for studentsto use in handbook fashion. General prin-ciples are stressed throughout, with emphasison the application of these principles to actualproblems. The proper use of units and aworkable method of converting units are alsostrongly emphasized.

Ready in June.

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INTRODUCTION TO THETHEORY OF EQUATIONS

By LOIS W. GRIFFITHS, AssociateProfessor of Mathematics, NorthwesternUniversity.

Designed for students with a background ofelementary work in plane trigonometry, planeanalytic geometry, and differential calculus,this book is an introduction to the theory ofequations, determinants, and matrices. Defi-nitions are clear and precise, and the expositiondetailed and logical. Second Edition.

Ready in June.

51 by 8j.

264 pages.

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652 pages.Probable price, $4.25

TEXTBOOK OFGENERAL ZOOLOGY

By FREDERICK A. WOLF, Professor ofBotany, Duke University; and FRED-ERICK T. WOLF, Assistant Professorof Biology, Vanderbilt University.

A comprehensive two volume discussion offungi, with the emphasis throughout bothbooks on the activities of fungi. Volume Icomprises a consideration of developmentalmorphology and taxonomy-the basic materialfor any comprehensive study of the subject.Volume II deals more specifically with theactivities of fungi and focuses attention on thereactions of a fungus.

Ready in June and Aug438pages. 6by9J.Volume IL6 by 91.

pust. Volume L$6.00.

Approximately 523 pages.Probable price, $7,00.

By WINTERTON C. CURTIS, ProfessorEmeritus of Zoology; and MARY J.GUTHRIE, Professor of Zoology; bothat the University of Missouri.

The fourth edition, like its predecessors, is awell-organized and detailed study of the factsconcerning the structure and functions ofanimals. A chapter on "The Organ-Systemsof Invertebrates" has been added; minoromissions and additions, reflecting changes inpresent-day emphasis, have been made; andthe already excellent illustrations have beenimproved, with many new ones added. FourthEdition.

Ready in August.

6 by 9,.

Approximately 766 pages.

Probable price, $4.50

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PHOTOGRAPH~tY IN SCIENCECompetition & Salon

Purpose and Nature. The Photography in Science Exhibition,sponsored jointly by the Division of Graphic Arts of THESMITHSONIAN INSTITUTION and THE SCIENTIFICMONTHLY, is designed to bring together the various techniquesof photography used by scientists in all fields of science and therebyextend its possibilities for development as a basic tool in researchand teaching. While unusual contrasts and pleasing compositionare important factors in other fields, the utilization ofnew techniquesof photography for the discovery or presentation of scientific data,scientific principles, and the dissemination of these ideas to allscientists will be stressed as the purpose of this salon. Scientistseverywhere are cordially invited to participate.

Eligibility. Membership in the A.A.A.S. is not required. Scientists actively engagedin teaching at all levels, in research and development, or scientists engaged in privatepractice or consulting, are eligible to submit entries.

Kinds of Prints. The exhibition will be composed of two divisions: Black andwhite and color. Black and white prints may be any size up to i6 x to inchesand color slides or transparencies should not exceed 31 x 41 inches.

Dates. Entries will be received in Washington from September 15 to October I5.The accepted entries will be hung in the Smithsonian Institution from November ito 30. They will then be shipped to Chicago for display at the International ScienceExhibition of the A.A.A.S. from December 2.6-3 i. At that time awards for the twodivisions will be announced. A selection of the prints will be published in theJanuary, I948, SCIENTIFIC MONTHLY.

No Entry Fee Required. No entry fee is required, but all entries must be sentprepaid and will be returned express collect at the close of the exhibition.

information and Entry Blanks. For information and entry blanks write to:

The Editor

The Scientific Monthly1515 Massachusetts Ave., N.W.

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