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.3SEPTEMBER 1954 hAaO SEPTEMBER 1954 11A

SLEEPING ACCOMMODATIONS AT 121st AAAS MEETINGBerkeley, California, December 26-31, 1954

The hotel, motel, and dormitory sleeping accommodations-their rates and the application coupon below-are for your convenience in making room reservations in Berkeley. Please send your application directly to theAAAS Housing Bureau and thereby avoid delay and confusion. The experienced Bureau will make assignmentspromptly; a confirmation will be sent you in two weeks or less. Single rooms may become scarce; double roomsfor single occupancy cost more; if possible, share a twin-bedded room with a colleague-and also save. Mail yourapplication now to secure your first choice of desired accommodations. All requests for reservations must give adefinite date and estimated hour of arrival and also probable date of departure.

HOTELS SINGLE DOUBLE TWIN SUITEClaremont 5.00-11.00 8.00-13.00 8.00-13.00 14.00-20.00Durant 4.00- 7.00 6.00- 9.00 6.50-10.00 10.00-16.00Shattuck 5.00-10.00 7.00-10.00 7.50-10.00 10.00-18.00Other hotels 3.00- 5.00 3.50- 5.00 4.00- 6.50 7.00-10.00

(Note: Most hotels have singles without private bath at $2.00-$3.50 per night)MOTELS FAMILY ROOMS

Berkeley Plaza 5.00 6.00 7.00 8.50-12.00California 4.00- 4.50 4.50- 5.00 5.50 6.00- 7.00Golden Bear 4.50- 5.00 5.00- 7.00 6.00- 8.00 7.50-10.00Other motels 4.00- 5.00 4.00- 6.00 5.50- 8.50 6.00-12.00

Dormitory Accommodations: NOTE: The 766 units in the University of California dormitories are primarily for students,younger faeulty members, and those not on expense accounts. Occupancy, two persons per room; rate, $2.00 the first night,$1.00 per night thereafter, per person.

International House: Singles only, without private bath, $2.50 per night.For a discussion of the headquarters of the participating societies and sections, please see Association Affairs, Science, July 23, orThe Scientific Monthly, August.

THIS IS YOUR HOUSING RESERVATION COUPON - . -AAAS Housing Bureau2223 Fulton Street Date of Application ................................Berkeley 4, CaliforniaPlease reserve the following accommodations for the 121st Meeting of the AAAS in Berkeley, Dec. 26-31, 1954:

First Choice .Second Choice ................... Third Choice(State name of hotel, motel, or other)

...... Single Room Desired Rate ....... Maximum Rate ....... R OOMDEPOSITl........Double-bedded Room Desired Rate ....... Maximum Rate.$5.00 per reservation or

...... Twin-bedded Room Desired Rate ....... Maximum Rate .$10.00 per room (re-........Suite ..........Desired Rate ....... .Maximum Rate .......funded if cancelled before.Suite Desired Rate . Maximum Rate . ~~~~~Dec.17)...... Dormitory Unit(s)-two persons per room at $2.00 each first night, $1.00 per Make checks payable to

night thereafter. "AAAS Housing Bureau."

The name and address of each jierson, including yourself, must be listed. Attach list if this space is insufficient.

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DATE OF ARRIVAL. ................ DEPARTURE DATE.(These must be indicated-add approximate hour, a.m. or p.m.)

NAME ...............................:........................1'as' p'.......t.e.............................(Individual requesting reservation) (please print or type)

ADDRESS ........ ..........................................................................(Street) (City and Zone) (State)

My society (or sectional interest) is: ....................................................................I (will) (will not) have an automobile at the Meeting.

Mail this now to the Housing Bureau (address above). Enclose hotel or motel room deposit. Make checks payable toAAAS HOUSING BUREAU. Rooms will be assigned and confirmed in order of receipt of reservation.

12A SCIENCE, 'VOL. 120

---------------- SEX IN M IC ROOR GANIS S-------------------Editorial Committee

D. H. WENRICH, University of Pennsylvania, ChairmanIVEY F. LEWIS, University of VirginiaJOHN R. RAPER, Harvard University

6 x 9 inches, 362 pages, 59 illustrations, 1 1 tables, clothbound, 1954Author and Subject Indexes, Bibliographies

Price $5.75, AAAS Members' prepaid order price $5.00.A symposium volume of the American Association for the

Advancement of ScienceA distinguished group of workers in this field presents the evidence for "sex" in the

principal groups of microorganisms. There has been some expansion of the material pre-sented at the symposium in Philadelphia to round out the volume.

Morphological, genetic, and physiological considerations are covered in a frameworkwhich will make the exciting new discoveries in this subject more meaningful to themany scientists following developments in this important area.

TABLE OFGenetic Recombination in Bacterial Viruses

Sex in Bacteria: Genetic Studies, 1945-1952

Sex in Bacteria: Evidence from Morphology

Life Cycles, Sexuality, and Sexual Mechanismsin the Fungi

Sexual Reproduction in Diatoms

Sex in Unicellular Algae

Sex in Protozoa: A Comparative Review

Mating Type Determination in Parameciumaurelia: A Study in Cellular Heredity

Mating Substances and the Physiology of Fertili.zation in Ciliates

CONTENTSN. VISCONTI,Carnegie Institution of WashingtonCold Spring Harbor, N. Y.

JOSHUA LEDERBERG,University of Wisconsinand E. L. TATUM,Stanford University

W. G. HUTCHINSON,University of Pennsylvaniaand HENRY STEMPEN,Jefferson Medical College

JOHN R. RAPER,Harvard University

RUTH PATRICK,Academy of Natural Sciences of Philadelphia

RALPH A. LEWIN,National Research CouncilHalifax, N. S.

D. H. WENRICH,University of Pennsylvania

DAVID L. NANNEY,University of MichiganCHARLES B. METZ,Florida State University

Comments on the Origin and Evolution of "Sex" D. H. WENRICH

American Association for the Advancement of Science1515 Massachusetts Avenue, NW, Washington 5, D. C.

English Agents: Bailey Bros & Swinfen, Ltd., 46 St. Giles High Street, London, W.C.23________SETME1954 ______,____--A-----------------------------------------------------------------------Z"

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3 SEPTEMBER 1954 13Ab

Ion TransportAcross MembranesIncorporating Papers Presented at aSymposium Held at the College of Physi-cians and Surgeons, Columbia University,

October 1953

HANS T. CLARKE, EditorDAVID NACHMANSOHN, Associate Editor

June 1954, xii, 298 pages, illustrated, $7.50

CONTENTS:Notes on the Work of Jacques Loeb

By W. J. V. OSTERHOUTIon Transport Across Biological Membranes

By HANS H. USSINGElectrical Processes in Nerve Conduction

By A. F. HUXLEYThe Generation of Bioelectric Potentials

By IRWIN B. WILSON and DAVIDNACHMANSOHN

Some Optical Observations on the InteractionBetween Acetyl Cholinesterase and Its Sub-strateBy S. L. FRIESS, J. J. BLUM, and M. F.MORALES

Ion Permeability of the Red CellBy A. K. PARPART and J. F. HOFFMAN

Renal Mechanisms of Electrolyte TransportBy GILBERT H. MUDGE

Membrane Permeability and Electrical PotentialBy RANSOM B. PARLIN and HENRY EYRING

Transport of Ions Through Biological Mem-branes from the Standpoint of IrreversibleThermodynamiiesBy JOHN G. KIRKWOOD

Transport of Ions Across Charged MembranesBy GEORGE SCATCHARD

Electrochemical Studies with Model MembranesBy KARL, SOLLNER

Theory of Protein SolutionsBy TERRELL L. HILL

Interaction of Proteins and Ions with SpecialReference to Mercury Derivatives of Mer-captalbuminBy JOHN T. EDSALL

The Specificity of Metal-Protein InteractionsBy FRANK R. N. GURD

Equilibrium and Sedimentation of UnchargedParticles in Inhomogeneous Electrical FieldsBy P. DEBnE

Author Index-Subject Index.

Academic Press Inc., Publishers125 East 23 Street, New York 10, N. Y.

NEW REPRINTSNow Available

G. Lindau et P. Sydow

THESAURUS LITTERATURAE MY-COLOGICAE ET LICHENOLOGICAERATIONE HABITA PRAECIPUE OM-NIUM QUAE ADHUC SCRIPTA SUNTDE MYCOLOGIA APPLICATA QUEMCONGESSERUNT G. LINDAU ET P.SYDOW

5 volumes, Berlin, 1908-173,652 pages

Cloth bound set, $100.09Paper bound set, 90.00

The first three volumes of this standard work, published inGermany during 1908-15, consist of a carefully compiledrecord of all known publications on mycology (includinglichenology and plant pathology) up to and including 1910.Listings are made chronologically by authors.

Two additional volumes present the same material topi-cally under such headings as geographical distribution.fungus groups, crops serving as hosts, etc. This set, loingout of print, is invaluable to workers in mycology and plantpathology, supplying the necessary historical backgroundthrough its bibliography.

THE ZOOLOGICAL RECORD

Volumes I-XX, 1864-1883Cloth bound set, $450.00Paper bound set, 435.00Single volumes, paper bound, each $22.50

The Zoological Record was first published in 1864, and thebibliography has since appeared in an unbroken series.

The first twenty volumes of the Record to be reprintedcontain references to zoological literature relating to theyears 1864 to 1883 and, whereas modern voluimes containpurely bibliographical details, these early voluimes informthe reader as fully as possible what he might expect tofind in any journal or paper mentioned. They are, in fact,very readable short abstracts, containing diagnoses of newgenera, and even critical remarks, occasionally, on currentwork.

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3 SEPTEMBER 1954

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15A

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Biologist, M.S. Itesearch and experience in botanical field, es-pecially mycology, plant diseases, fruit growing; in medical labora-tory; library. Now enigaged in bacteriology-parasitology research.l)esires challenging position in research, teaching. Box 236,SCIENCE. X

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Microbiologist-Immunologist: D.V.M., Ph.D. 34. PresentlyAssoc. Prof. state university. I)esires research or research andteaching position. Ten years infectious disease research, teaching.East preferred. Box 237, SCIENCE. 9/10

Parasitologist, male, 30. M.S.P.H., Teachinig and TuberculosisLab. experieilce. l)esires opportunity to broaden experietice indiversified fields. Box 235, SCIENCE. 9/3

Research Administration: M.A. (Mathematics, Physics) plus 3years graduate sttudy Germany (Physics, Mathematics) with 10years teaching experience and 6 years experienice research admiti-istration desires positioni in inidtustry or with research organization.Box 234, SCIENCE. 9/3

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POSITIONS OPEN

(a) Pharmacologist, preferahly phy sician; senior research positioll;onle of leading companies. (b) Medically trainie(d mycologist for al-pooitment of inistructori or assistalnt professor; duties. half-timeteachinig, half-time research; $5000 to $7000. (c) Medical copy-writer; onie of lea(liig pharmaceuitical companlies; $8000-$8500.(d) Biochemist, Ph.)., qualifie(d microbiology; research inivolvingmechanism of microbial physiology in relation to action of anti-hiotics; university research department. (e) Director, producteducation; physician no longei initerested clinical medicinie, com-p)etent writer required; $12,000. S9-1 Medical Bureau, (BturneiceLarsoni, Director) Palmolive Building, Chicago. X

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Technicians wanted. We have openiitngs in our micro-slide lahora-torv for onie assistanit atnd two experienced technlicians. All arepermanent, full-time (40-hour week) positions with paid vacations,hospitalization inisturatnce, retiremeint pensioni anid other employeebenefits: (1) Assistant embryologist; must have college degree withmajor in zoology or biology, inicluding some courses in embryology;experience in slide making niot required. (2) Embryology techni-cian; must be experienced in making serial sections of chick anid pigembryos, and in handling all phases of technique work in verte-brate and invertebrate embryology. (3) Botany technician; re-quirements include grod training in morphology and experieilcein making a wide range of botanical slides, including paraffini anidcelloidin sectionis and whole mounts. Preference given to appli-cants now residing within 500 miles of Chicago. Write to C.Blair Coursen, General Biological Supplv House, Inc., 761 East69th Place, Chicago 37, Illinois. X

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