COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY

VOLUME XXV

COLD SPRING HARBOR SYMPOSIA

ON Q UANTITA T I V E BIOLOGY

Founded in 1933

by REGINALD G. HARRIS

Director of the Biological Laboratory

1924 to 1936

The Symposia were organized and managed by Dr. Harris until his death. Their continued use- fulness is a tribute to the soundness o/ his vision.

The Symposium volumes

are published by the Long Island Biological Association

as a part of the work of the Biological Laboratory

Cold Spring Harbor, L. I., New York

COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY

VOLUME XXV

Biological Clocks

THE BIOLOGICAL LABORATORY

COLD SPRING HARBOR, L. I., NEW YORK

1960

COPYRIGHT �9 1961 BY

THE BIOLOGICAL LABORATORY

LONG ISLAND BIOLOGICAL ASSOCIATION, INC.

All rights reserved. This book may not be reproduced

in whole or in part except by reviewers for the public

press without written permission from the publisher.

69166

PRINTED BY

WAVERLY PRESS, INC., BALTIMORE, MARYLAND, U. S. A.

Foreword

While daily rhythms have been studied systematically for many years, there has been a most remarkable outburst of interest in the subject during the past ten years. This growth of interest is due, almost entirely, to the elegant experimental demonstrations that birds, bees, and many other animals orient or "navigate" using the position of the sun as a guidepost, and compensating for its movement in time with the use of an internal chronometer. Rapid advances have been seen in studies of rather diverse phenomena in a wide variety of organisms from single cells through higher plants and animals.

By bringing together leading investigators from throughout the world who are intimately concerned with the broad array of phenomena classified under the general topic "Biological Clocks", it is hoped that this year's Symposium may serve as a unifying influence on the entire field of study.

The program this year was organized by a committee consisting of C. S. Pitten- drigh (Chairman), J. Aschoff, V. G. Bruce, E. Biinning, D. R. Griffin, and J. W. Hastings. Serving as chairmen of the program sessions were: C. S. Pittendrigh, E. Bfinning, J. Aschoff, S. B. Hendricks, V. G. Bruce, H. Kalmus, O. H. Schmitt, A. D. Lees, K. V. Thimann, C. P. Richter, F. Halberg, R. Bfinsow, D. R. Griffin, K. S. Rawson, K. Hoffmann, A. D. Hasler, and F. A. Brown, Jr. The Laboratory is indeed grateful to all of these gentlemen for their efforts in organizing and con- ducting the program.

The Laboratory is pleased to acknowledge support of the Symposium by The Carnegie Corporation of New York, The Rockefeller Foundation, Institute of Oceanography and Marine Biology, National Science Foundation, Office of Naval Research under the auspices of the American Institute of Biological Sciences, United States Public Health Service, and the United States Air Force monitored by the Office of Scientific Research of the Air Research and Development Com- mand.

This year, preparation of the volume for publication was supervised by our editor, Leonora Frisch, assisted by Ruth Schalet and Ethel Burtch. The very difficult task of indexing was handled by Dr. C. S. Pittendrigh and his colleagues at Princeton University. To all of these people, the Laboratory owes a debt of gratitude.

The meetings, held from the 5th through the 14th of June, 1960, were attended by 150 scientists, including 31 from abroad.

ARTHUR CHOVNICK

LIST OF PREVIOUS VOLUMES

Volume I (1933) Surface Phenomena, 239 pp. Volume II (1934) Aspects of Growth, 284 pp. Volume III (1935) Photochemical Reactions, 359 pp. Volume IV (1936) Excitation Phenomena, 376 pp. Volume V (1937) Internal Secretions, 433 pp. Volume VI (1938) Protein Chemistry, 395 pp. Volume VII (1939) Biological Oxidations, 463 pp. Volume VIII (1940) Permeability and the Nature of Cell Membranes, 285 pp. Volume IX (1941) Genes and Chromosomes: Structure and Organization, 315 pp. Volume X (1942) The Relation of Hormones to Development, 167 pp. Volume XI (1946) Heredity and Variation in Microorganisms, 314 pp. Volume XII (1947) Nucleic Acids and Nucleoproteins, 279 pp. Volume XII I (1948) Biological Applications of Tracer Elements, 222 pp. Volume XIV (1949) Amino Acids and Proteins, 217 pp. Volume XV (1950) Origin and Evolution of Man, 425 pp. Volume XVI (1951) Genes and Mutations, 521 pp. Volume XVII (1952) The Neuron, 323 pp. Volume XVIII (1953) Viruses, 301 pp. Volume XIX (1954) The Mammalian Fetus: Physiological Aspects of Development,

225 pp. Volume XX (1955) Population Genetics: The Nature and Causes of Genetic Varia-

bility in Populations, 346 pp. Volume XXI (1956) Genetic Mechanisms: Structure and Function, 392 pp. Volume XXII (1957) Population Studies: Animal Ecology and Demography, 437 pp. Volume XXI I I (1958) Exchange of Genetic Material : Mechanisms and Consequences,

450 pp. Volume XXIV (1959) Genetics and Twentieth Century Darwinism, 321 pp.

vi

SOME SYMPOSIUM PARTICIPANTS

Top row: H. M. Webb, H. Kalmus; W. Braemer, K. Hoffmann, A. D. Hasler; F. Halberg, A. Sollberger, H. Kalmus, A. D. Lees.

Second row; K. Klotter, Th. Hellbrtigge, J. Aschoff, C. S. Pittendrigh, D. S. Lehrman; A. Wolfson, A. J. Marshall; W. Braemer, B. J. Oetting, H. J. Ball, G. Birukow.

Third row: Th. Helbriigge, E. Segal, B. Schwemmle; H. M. Webb, J. Harker, M. Sandeen; F. A. Brown, Jr., M. B. Wilkins, G. Birukow, E. Biinning.

Bottom row: A. Barnett, B. Sweeney, M. Lindauer; K. S. Rawson, O. H. Schmitt; S. B. Hendricks, J. E. Flynn, K. V. Thimann.

SOME SYMPOSIUM PARTICIPANTS

Top row: F. W. Went, J. Aschoff; S. K. Roberts, P. DeCoursey; C. S. Pittendrigh, A. Chovnick, E. Bfinning. Second row: L. Frisch, V. G. Bruce; F. A. Brown, Jr., G. Birukow; A. D. Lees, C. E. Jenner. Th i rd row: H. 0. Schwassmann, A. Chovnick, M. B. Wilkins, M. Renner, H. Hayes; D. Kennedy, M. B. Wilkins, M. C.

Lobban; H. G. Wallraff, D. M. A. Mercer, A. Sollberger, F. A. Brown, Jr. Bot tom row: K. Hoffmann, C. Hauenschild, P. DeCoursey, P. S. Corbet, J. Aschoff, J. L. Cloudsley-Thompson;

H. Kalmus, A. Chovnick, 0. H. Schmitt, H. E. Savely, J. T. Enright; S. Mori, M. Kato.

(Photographs by Robert Beaumont)

List of Those Attending the Symposium ADLER, HELMUT E., American Museum of Natural

History, New York City AKEY, ALICE, Adelphi College, Garden City, New

York ALEXANDER, MARY L., University of Texas, Houston,

Texas ANDERSON, PAUL, Columbia University, New York

City ASCHOFF, J~RGEN, Max-Planck-Institut ffir Verhaltens-

physiologic, Erling-Andechs/Obb., Germany BALL, HAROLD J., University of Nebraska, Lincoln,

Nebraska BARLOW, JOHN S., Massachusetts Institute of Tech-

nology, Cambridge, Massachusetts and Massachu- setts General Hospital, Boston, Massachusetts

BARNETT, AUDREY, Indiana University, Bloomington, Indiana

BARNWELL, FRANKLIN H., Northwestern University, Evanston, Illinois

BARTELL, CLELMER K., Duke University, Durham, North Carolina

BARTH, ROBERT, Harvard University, Cambridge, Massachusetts

BARTON, ALEXANDER, The Stony Brook School, Stony Brook, New York

BENNETT, MIRIAM F., Sweet Briar College, Sweet Briar, Virginia

BIANCHI, CARLA, Northwestern University, Evanston, Illinois

BIRUKOW, GEORG, Zoologisches Institut der Universi- titt, GSttingen, Germany

BLAKESLEE, ALTON, The Associated Press, New York City

BLISS, DOROTHY E., The American Museum of Natural History, New York City

BRAEMER, WOLFGANG, Max-Planck-Institut, Seewiesen, fiber Starnberg/Obb., Germany

BRANDT, WILLIAM H., Oregon State College, Corvallis, Oregon

BREHME, KATHERINE, Adelphi College, Garden City, New York

BROWN, CLIFFORD, National Film Board of Canada, Montreal, Canada

BROWN, FRANK A., JR., Northwestern University, Evanston, Illinois

BRUCE, VICTOR G., Princeton University, Princeton, New Jersey

B?3NNING, ERWlN, Botanisches Institut, Universitiit Tiibingen, Germany

B?3NSOW, ROBERT C., Pflanzenphysiologisches Institut der Universitiit, G6ttingen, Germany

BUTNER, ALFRED, Jamaica, New York CARR, ARCHIE, University of Florida, Gainesville,

Florida ix

CAVANAGH, JAMES, Garden City, New York CHOVNICK, ARTHUR, Biological Laboratory, Cold

Spring Harbor, New York CLOUDSLEY-THOMPSON, J. L., University of London,

Ydng's College, London, England COLLINS, WALTER, Colorado State University, Fort

Collins, Colorado CONKLIN, MARIE E., Adelphi College, Garden City,

New York CORBET, PHILIP S., East Africa Virus Research Insti-

tute, Entebbe, Uganda, East Africa DECouRSEY, PATRICIA, University of Wisconsin, Madi-

son, Wisconsin EHRET, CHARLES F., Argonne National Laboratory,

Leniont, Illinois ENGELMANN, FRANZ, Albert Einstein College of Medi-

cine, New York City ENRIGHT, J. T., University of California, LaJolla,

California FAY, ANTHONY F., Flushing, New York FINGERMAN, MILTON, Tulane University, New Orleans,

Louisiana FLYNN, JOHN E., Office of Naval Research, New York

City FOLK, G. EDGAR, State University of Iowa, Iowa City,

Iowa FRISCH, LEONORA, Biological Laboratory, Cold Spring

Harbor, New York GALINSKY, IRVING, Hofstra College, Hempstead, New

York GALLER, S. R., Omce of Naval Research, Washington,

D.C. GAY, HELEN, Carnegie Institution of Washington, Cold

Spring Harbor, New York GOULD, EDWIN, Tulane University, New Orleans,

Louisiana GRACE, EDWIN J., Grace Clinic Group, Brooklyn, New

York GRIFFIN, DONALD R., Harvard University, Cambridge,

Massachusetts GUYSELMAN, J. BRUCE, Carleton College, Northfield,

Minnesota HALBERG, ERNA, University of Minnesota Medical

School, Minneapolis, Minnesota HALBERG, FRANZ, University of Minnesota Medical

School, Minneapolis, Minnesota HAMILTON, WILLIAM J., California Academy of Sci-

ences, San Francisco, California HAMNER, KARL C., University of California, Los

Angeles, California HAN, JACK, State University of New York, Syracuse,

New York

X LIST OF THOSE ATTENDING THE SYMPOSIUM

HARKER, JANET E., Zoological Laboratory, Cambridge, England

HASLER, ARTHUR D., University of Wisconsin, Madi- son, Wisconsin

HASTINGS, ANTOINETTE, American Association for the Advancement of Science, Westbury, New York

HASTINGS, J. WOODLAND, University of Illinois, Urbana, Illinois

HAUENSCHILD, C., Zoologisches Institut der Universi- t~t, Freiburg/Br., Germany

HAYES, HELEN, Office of Naval Research, Washington. D.C.

HELLBRiJGGE, THEODOR, Kinderpoliklinik der Universi- t/it, M0.nchen, Mr:richeR, Germany

HELMS, CARL W., Massachusetts Audubon Society, South Lincoln, Massachusetts

HENDRICKS, STERLING B., V. S. Department of Agri- culture, Beltsville, Maryland

HIGHKIN, n. R., California Institute of Technology, Pasadena, California

HILLS, ALICIA, Life Magazine, New York City HOAGLAND, HUDSON, The Worcester Foundation for

Experimental Biology, Shrewsbury, Massachusetts HOFFMANN, KLAUS, Max-Planck-Institut ftir Verhalt-

ensphysiologie, Erling-Andechs/Obb., Germany, and Princeton University, Princeton, New Jersey

HoPwooD, JOSEPH, Colorado State University, Fort Collins, Colorado

HUBBARD, HENRY, Newsweek, New York City ISAAC, DONALD, University of California, Berkeley,

California JACOBS, GEORGE, National Aeronautics and Space Ad-

ministration, Washington, D. C. JENNER, CHARLES E., University of North Carolina,

Chapel Hill, North Carolina KAHN, DAVID, Newsday, Garden City, New York KALMUS, HANS, University College London, London,

England KARAKASHIAN, MARLENE W., University of California,

Los Angeles, California KATO, MASARU, Washington State University, Pullman,

Washington KAUFMANN, BERWIND N., University of Mississippi

Medical Center, Jackson, Mississippi KAUFMANN, BERWIND P., Carnegie Institution of Wash-

ington, Cold Spring Harbor, New York KENNEDY, DONALD, Syracuse University, Syracuse,

New York KEBNAGHAN, ROY PETER, Biological Laboratory, Cold

Spring Harbor, New York KLOTTER, KARL, Institut fflr Angewandte Mechanik,

Darmstadt, Germany KRAMER, SOL, State University College on Long Island,

Oyster Bay, New York KRAUSS, MARIAN, Biological Laboratory, Cold Spring

Harbor, New York

KRIS, E. CHRISTINE, Cambridge, Massachusetts LARSEN, VICTOR, Adelphi College, Garden City, New

York LEES, ANTHONY D., Agricultural Research Council,

Cambridge, England LEHRMAN, DANIEL S., Rutgers University, Newark,

New Jersey LEINWEBER, FRANZ J., Johns Hopkins University,

Baltimore, Maryland LEINWEBER, LUPE, Baltimore, Maryland LIENAU, CARL, Columbia University, New York City LINCOLN, RICHARD G., Long Beach State College, Long

Beach, California LINDAUER, MARTIN, Zoologisches Institut der Universi-

tiit M0.nchen, Miinchen, Germany LOBBAN, MARY C., Medical Research Council :Labora-

tories, London, England MACDOWELL, E. C., Biological Laboratory, Cold Spring

Harbor, New York MALM, MIGNON, Princeton University, Princeton, New

Jersey MARSHALL,'A. J., Monash University, Victoria, Aus-

tralia MENAKER, MICHAEL, Harvard University, Cambridge,

Massachusetts MERCER, DERWENT ~. A., Physical Laboratory, The

University, Southampton, England MILLMAN, EDWARD, Grumman Aircraft Engineering

Corporation, Bethpage, New York MINIS, DOROTHY, Princeton University, Princeton, New

Jersey MIYAKE, AKIO, Osaka City University, Osaka, Japan MOE, GORDON K., Masonic Medical Research Labora-

tory, Utica, New York MORI, SYUITI, Zoological Institute, Kyoto University,

Kyoto, Japan MUKAI, FRANK, Carnegie Institution of Washington,

Cold Spring Harbor, New York NOVICK, ALVIN, Yale University, New Haven, Con-

necticut NOWOSIELSKI, JOZEF, Cornell University, Ithaca, New

York 0ETTING, BONNALIE J., Northwestern University,

Evanston, Illinois 0L~VE, JOHN R., American Institute of Biological

Sciences, Washington, D. C. PALMER, JOHN, Northwestern University, Evanston,

Illinois PETROPULOS, STEPHEN F., Princeton University, Prince-

ton, New Jersey PITTENDRIGH, COLIN S., Princeton University, Prince-

ton, New Jersey PROKOP, BARBARA, Biological Laboratory, Cold Spring

Harbor, New York RAWSON, KENNETH S., Swarthmore College, Swarth-

more, Pennsylvania

LIST OF THOSE ATTENDING THE SYMPOSIUM xi

RAWSON, KENNETH S., MRs., Swarthmore College, Swarthmore, Pennsylvania

RENh'ER, MAX, Zoologisches Institut der Universitiit, Miinchen, Germany

RI(?ttTER, CURT P., The Johns Hopkins Hospital, Balti- more, Maryland

ROBERTS, SHEPHERD K., Princeton University, Prince- ton, New Jersey

SAND EEN, MURIEL I., Duke University, Durham, North Carolina

SAVELY, HARVEY E., U. S. Air Force, Washington, D.C.

SCHALET, RUTH, Biological Laboratory, Cold Spring Harbor, New York

SCHARRER, BERTA, Albert Einstein College of Medicine, New York City

SCHARRER, ERNST, Albert Einstein College of Medicine, New York City

SCHI'~ELE, GEORGE A., Princeton University, Princeton, New Jersey

SCHEFANO, ANTHONY, Hofstra College, Hempstead, New York

SC~IDT-KOENIG, KLAUS, Max-Planck-Institut far Verhaltensphysiologie, Wilhehnshaven, Germany, and Duke University, Durham, North Carolina

SCHMITT, OTTO H., University of Minnesota, Minne- apolis, Minnesota

SCHMITT, OTTO H., MRS., University of Minnesota, Minneapolis, Minnesota

SCHWASSMANN, HORST 0., University of Wisconsin, Madison, Wisconsin

SCH~VEMMLE, BERTHOLD, Pflanzenphysiologisches Insti- rut der Universiti~t, GSttingen, Germany

SEGAL, EARL, Kansas State Teachers College, Emporia, Kansas

SHAPIRO, ARTHUR, New York State University, Brook- lyn, New York

SHAPIRO, SEYMOUR, Brookhaven National Laboratory, Upton, New York

SIMON, EDWARD, Carnegie Institution of Washington, Cold Spring Harbor, New York

SIROHI, G. S., University of California, Los Angeles, California

SMOLKER, ROBERT, State University of New York, Oyster Bay, New York

SOKOLOFF, ALEXANDER, William H. Miner Agricultural Research Institute, Chazy, New York

SOKOLOFF, ALEXANDER, MB.S., William H. Miner Agri- cultural Research Institute, Chazy, New York

SOLLBERGER, ARNE, Caroline Institute, Stockholm, Sweden

SUCKLING, EUSTACE, State University of New York Medical College, Brooklyn, New York

SWADE, RICHARD H., Princeton University, Princeton, New Jersey

SWEENEY, BEATRICE M., University of California, LaJolla, California

TALL, BENITA, American Institute of Biological Sci- ences, Washington, D. C.

THIMANN, KENNETH V., Harvard University, Cam- bridge, Massachusetts

THORNBURG, WAYNE, Dartmouth Medical School, Hanover, New Hampshire

TOLLES, WALTER, Institute of Oceanography and Marine Biology, Oyster Bay, New York

~VALLRAFF, HANS G., Max-Planck-Institut ftir Verhalt- ensphysiologie, Wilhelmshaven, Germany

WEBB, H. MARGUERITE, Stazione Zoologica, Napoli, Italy

WEITZMAN, MARY, Albert Einstein College of Medicine, New York City

WELLS, G. P., University College London, London, England

WENT, F. W., Missouri Botanical Garden, St. Louis, Missouri

WEVER, Ri2TGER, Max-Planck-Institut ftir Verhaltens- physiologic, Erling-Andechs/Obb, Germany

WILDER, JOSEPH, Society for Biological Rhythms, Stockholm, Sweden

WILKINS, MALCOLM B., University of London King's College, London, England

WISPY, WARREN, University of Miami, Miami, Florida WOLF, WILLIAM, New York City WOLFSON, ALBERT, Northwestern University, Evans-

ton, Illinois WULFF, VERNER J., Masonic Medical Research Lab-

oratory, Utica, New York

Contents

Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v List of Participants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix BttiNrNO, ERWIN. Opening Address: Biological Clocks . . . . . . . . . . . . . . . . . . . . . 1

GENERAL PROPERTIES OF CIRCADIAN RHYTHMS

ASCHOFF, J. Exogenous and Endogenous Components in Circadian Rhythms. 11 BRUCE, V. G. Environmental Entra inment of Circadian Rhythms . . . . . . . . . . 29 DECouRsEY, P. Phase Control of Activity in a Rodent . . . . . . . . . . . . . . . . . . . . 49 BROWN, F. A., JR. Response to Pervasive Geophysical Factors and the Biological

Clock Problem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 MERCER, D. M. A. Analytical Methods for the Study of Periodic Phenomena

Obscured by Random Fluctuations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 S~VEENEY, B., AND J. W. HASTINGS. Effects of Temperature upon Diurnal

Rhythms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 RAWSON, K. S. Effects of Tissue Temperature on Mammalian Activity

Rhythms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 WILKINS, M. B. The Effect of Light upon Plant Rhythms . . . . . . . . . . . . . . . . . . 115

METABOLIC ASPECTS OF CIRCADIAN RHYTHMS

HASTINGS, J. W. Biochemical Aspects of Rhythms: Phase Shifting by Chem- icals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

SWEENEY, B. The Photosynthetic Rhy thm in Single Cells of Gonyaulax

polyedra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 EHRET, C. F. Action Spectra and Nucleic Acid Metabolism in Circadian

Rhythms at the Cellular Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

MODELS FOR CIRCADIAN RHYTHMS

PITTENDRIGH, C. S. Circadian Rhythms and the Circadian Organization of Living Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

KLOTTER, K. General Properties of Oscillating Systems . . . . . . . . . . . . . . . . . . . . 185 KLOTTER, K. Theoretical Analysis of Some Biological Models . . . . . . . . . . . . . . . 189 WEVER, R. Possibilities of Phase-control, Demonstrated by an Electronic

Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 SCHMITT, O. H. Biophysical and Mathematical Models of Circadian Rhythms 207 KALMUS, H., AND L. A. WIGGLESWORTH. Shock Excited Systems as Models for

Biological Rhythms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 EHRET, C. F., AND J. S. BARLOW. Toward a Realistic Model of a Biological

Period-measuring Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217

CIRCADIAN RHYTHMS IN PHOTO- AND THERMOPERIODISM

WENT, F. W. Photo- and Thermoperiodic Effects in Plant Growth . . . . . . . . . . 221 HIGHKIN, H. R. The Effect of Constant Temperature Environments and of

Continuous Light on the Growth and Development of Pea Plants . . . . . . 231 SCHWEMMLE, B. Thermoperiodic Effects and Circadian Rhythms in Flowering

of Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 I-IENDRICKS, S. B. Rates of Change of Phytochrome as an Essential Factor

Determining Photoperiodism in Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245 BiJNNING, E. Circadian Rhythms and the Time Measurement in Photo-

periodism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 xii

CONTENTS xiii

B?)NSOW, R. C. The Circadian R h y t h m of Photoperiodic Responsiveness in K a l a n c h o ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257

LEES, A. D. Some Aspects of Animal Photoperiodism . . . . . . . . . . . . . . . . . . . . . 261 HAMNER, K. C. Photoperiodism and Circadian Rhy thms . . . . . . . . . . . . . . . . . . . 269

CIRCADIAN RHYTHMS IN ANIMAL PHYSIOLOGY

HARKER~ J. Endocrine and Nervous Factors in Insect Circadian R h y t h m s . . . 279 HALBERG, F. Temporal Coordination of Physiologic Function . . . . . . . . . . . . . . 289 HELLBR~GGE, TIt. The Development of Circadian Rhy thms in Infants . . . . . . 311 LOBBAN, M. C. The Ent ra inment of Circadian Rhy thms in Man . . . . . . . . . . . 325 MoRI, S. Analysis of Environmental and Physiological Factors on the Daily

Rhythmic Activi ty of a Sea Pen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 333

ECOLOGICAL ASPECTS OF CIRCADIAN RHYTHMS

CLOUDSLEY-THoMPSON, J. L. Adapt ive Functions of Circadian Rhy thms . . . . 345 CORBET, P. S. Pat terns of Circadian Rhy thms in Insects . . . . . . . . . . . . . . . . . . 357 RENNER, M. The Contribution of the Honey Bee to the Study of Time-Sense

and Astronomical Orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361

CHRONOMETRY IN CELESTIAL ORIENTATION

Dedication to Gus tav Kramer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369 LINDAUER, M. Time-Compensated Sun Orientation in Bees . . . . . . . . . . . . . . . . 371 HOFFMANN, K. Experimental Manipulat ion of the Orientational Clock in

Birds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379 SCHMIDT-KOENIG, K. Internal Clocks and Homing . . . . . . . . . . . . . . . . . . . . . . . . 389 PARDI, L. Innate Components in the Solar Orientation of Littoral Amphipods. 395 BIRUKOW, G. Innate Types of Chronometry in Insect Orientation . . . . . . . . . . 403 BRAEMER, W. A Critical Review of the Sun-Azimuth Hypothesis . . . . . . . . . . . 413 HASLER, A. D., AND H. O. SCHWASSMANN. Sun Orientation of Fish a t Different

Latitudes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429 SCHWASSMANN, H. O. Environmental Cues in the Orientation R h y t h m of Fish. 443 WALLRAFF, H. G. Does Celestial Navigat ion Exist in Animals? . . . . . . . . . . . . . 451 SAUER, F., AND E. SAUER. Star Navigat ion of Nocturnal Migrating Birds . . . . 463 PAl)I, F. Orientation by Night: The Moon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 475

LONGER PERIODICITIES

FINGERMAN, M. Tidal Rhythmic i ty in Marine Organisms . . . . . . . . . . . . . . . . . . 481 HAUENSCHILD, C. Lunar Periodicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491 MARSHALL, A. J. Annual Periodicity in the Migrat ion and Reproduction of

Birds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499 WOLFSON, A. Regulation of Annual Periodicity in the Migration and Repro-

duction of Birds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 507