A NEW TECHNICONmicroslide cabinet for

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February 16, 1951

New!v Decilduous Forestsiston ~of Eastern N#orth. America

by E. Lucy Braun, Ph.D.~ ~~sfor ~~~~~~PRESIDENT, THE ECOLOGICAL SOCIETY

This text-the only one of its kind-presents the basic facts involvedin the ecology, succession, and geography of the deciduous forests ofeastern North America.

Virgin forests. The author spent 15 years and travelled 65,000 mfils instudying these original forest patterns, many of which are extinct to-

rence ~ ~~~day. As a result, this text will be a reliable source and reference asvirgin areas continue to disappear.

In its three parts, it presents the composition of virgin forests,analyzes and compares climax communities, traces the expansions andcontractions of the deciduous forest formation and its segregation intotypes, and demonstrates the genetic relations of its several parts.Of unusual value is the 22" x23" map of forest regions, which is

folded into the binding. (Additional copies printed on linen, suitablefor field work or framing, may be purchased separately: $1.50 per map.)

95 Illustrations-90 Tables-595 Pages-$1 0.00

Jew! Morphologyand TFaxonomny of Fungil

by Ernst A. Bessey, Ph.D.DEAN EMERITUS OF THE SCHOOL OF- GRADUATE STUDIES, MICHIGAN STATE COLLEGE

rhis is an orderly and complete treat. useful for those doing research in various LFLFLJ..,nt of the structures, life histories, and fields where a basic knowledge of fungi istssifications of all the important groups required.fungi. Containing the basic information, The new and specially prepared draw.forms the foundation for more intensive

dy ofspcializedgroups.ings are invaluable aids in the study ofWVritten by the foremost mycologist in th sujc.O graimoanestecountry today, it is a textbook and 96-page guide to the literature for the

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ASTROPHYSICS: A Topical SymposiumBy J. A. IIYNEK, Ohio State UIliversitv. McGraw-Hill Astronomical Series. In press

A symposium of papers treating "essentially all the active fields" of astrophysics. The fifteencontributors are leaders and authorities in their respective fields. The volume commemorates theFiftieth Anniversary of the Yerkes Observatory and reviews the progress in astrophysics duringthe half-century since the founding of the observatory. The book coimbines many of the featuresof a textbook, a handbook, a historical study, and a technical treatise.

IGNEOUS AND METAMORPHIC PETROLOGYBy FRANCIS J. TURNER, aind JEAN VERHOOGEN, University of California. In press

A unified treatment of the origin and evolution of rocks that have crystallized, or have been pro-foundly modified, at high temperatures. The material is based on field and petrographic data, andon the physico-chemical behavior of rock-forming minerals as determined by experiment and de-duced from thermodynamic theory.

ELECTRONICS. New 2nd EditionBy JACOB MILLMAN, College of the City of New York, and SAMIUEL SEELY, Syracuse Uni-versity. In press

A thorough revision and modernization of a highly successful text. The basic philosophy of thefirst edition of presenting physical electronics and engineering electronics side by side has beenretained. Wherever possible, the material is presented in a quantitative manner. The emphasisis on physical fundamentals, on ani introduction to commercial tubes, and on the analysis of theaction of these tubes as simple circuit elements. Rectifier circuits are considered in great detail.

ANATOMY OF THE CHORDATESBy CHARLES K. WEICHERT, University of Cincinnati. McGraw-Hill Publications in theZoological Sciences. In press

A text for the full-year's course in comparative anatomy of the vertebrates. It is a carefully pre-pared. book, presenting the subject in a readable, interesting manner, using illustrations as muchas possible to stimulate interest and clarify text material. The book discusses the classificationand natural history of the main groups of living animals making up the phylum Chordata. Achapter on development follows. Then, each org,an system is taken up separately and from acomparative point of view.

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Announcing the Forthcoming Publication ofTwo Geology Texts of Major Importance

IN HARPER'S GEOSCIENCE SERIESUnder the editorship Of CAREY CRONEIS

Ready March I

A TEXTBOOK OF GEOLOGYBy ROBERT M. GARRELS

ASSOCIATE PROFESSOR OF GEOLOGY, NORTHWESTERN UNIVERSITYThis important introductory text provides a distinctly new analytical approach to the study ofgeneral geology. Outstanding features of tlse work can be briefly sumnmarized as follows:1. A high degree of organic unity, achieved by utili7ing a developmental rather than a topicalapproach. The question of the age of the earth underlies the entire text.2. An approach primarily analytical rather than descriptive. Understanding of geologic processesis stressed, rather than cataloging their results or products.3. Scientific method is highlighted throughout, and graphical methods are extensively used.However, this quantitative mathematical treatment is simple enough for beginning students.4. Outstanding ill-ustrations, including more than 100 halftones and nearly 200 charts, graphs,and diagrams.

511 pages $5.00

Ready in April

STRUCTURAL GEOLOGY OF NORTH AMERICABy A. J. EARDLEY

PROFESSOR OF GEOLOGY, UNIVERSITY OF UTAHThis is the first book in any language to furnish a detailed description of the structural cvolu-tion of an entire continent. This monumental work is a unique publishing achievement. Its un-usual format (1 ¼4" x 8 ¼", with double-column pages) makes it equivalent in content to twoaverage volumes. It includes 16 paleotectonic maps in full color, and some 750 illustrations, manyof them prepared especially for the book. Its bibliography of approximately 700 carefully selecteditems is in itself a major contribution. The text covers the structural evolution of this continentin post-Proterozoic timne: the formation and constitution of the mountain systems, basins, arches,and volcanic archipelagos, the beveling of the highlands, and the filling of the basins. An utn-equalled text for advanced courses, and an inidispensable manutal and reference work for practic-ing geologists.

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SCIENCE, Vqd.- 113

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Emphasizes a practical approach- to discovery and trapping of oil and gas

PETROLEUM GEOLOGYBy KENNETH K. LANDES, University of Michigan. The only modern book covering all three divisions ofpetroleum geology-geological occurrences of oil and gas deposits, geographical distribution of oil and gas

deposits, and techniques for locating oil and gas. Gives important information on possible hydrocarbonsources of the future and organizes, synthesizes and critically evaluates the many theories developed to

explain the origin, migration, and accumulation of oil and gas. February 1931. 660 pages. 241 illus.Prob. $10.00.

Cowles CommissionMonograph No. 12

discusses question of choice

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SOCIAL CHOICE and INDIVIDUAL VALUES

By KENNETH J. ARROW, Stanford University. Deals with thequestion of whether it is possible to construct a social preferencefunction (as a guide to choice among alternatives) which reflects,in an objective and impartial manner, the preference of all in-dividuals in regard to these alternatives. Dr. Arrow uses themethods of symbolic logic in a rigorous attempt to establish alogical foundation for social welfare judgments. February 1931.99 pages. $2.50.

The FISCHER-TROPSCH and RELATED SYNTHESESIncluding a Summary of Theoretical and Applied Contact Catalysis.

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ELEMENTS of OPTICAL MINERALOGYAn Introduction to Microscopic Petrography

Part Il-DESCRIPTIONS of MINERALSWith special reference to Their Optic

and Microscopic Characters

Fourth edition by ALEXANDER N. WINCHELL, University ofWisconsin with the collaboration of Horace Winchell, Yale Uni-versity. Offers a description of minerals whose optical qualities aresufficiently well known to permit diagnosis by means of a micro-scope. January 1951. 31 pages. 427 illus. $12.50.Send for copies on approval.

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