The Macmillan Company IAnnounces . . I

Two THE AXONOMY OFNew VASCULAR PLANTSTitles GEORGE H. M. LAWRENCE

Professor of BotanyBailey Hortorium, Cornell University

Written by a well-known taxonomist, this text is designed for studentsin the beginning or intermediate courses in systematic botany. It pro-vides a comprehensive source of information on the theory, principles,and operating procedures followed in plant taxonomy plus an ac-counting of all of the families of plants known to grow in North Amer-ica. Professor Lawrence was a delegate on nomenclatorial matters tothe Seventh International Botanical Congress in Stockholm and re-visions in the International Rules of Botanical Nomenclature are in-cluded in his book. Published September 25.

r THE PRINCIPLES OFGENERAL BIOLOGY

MARY S. GARDINERProfessor of BiologyBryn Mawr College

Professor Gardiner's basic text for general biology courses presents abroad general picture of the principles underlying biological concepts

For and methods. It is a principles type of book rather than a descriptivestatement of factual material. Physiology of function has been stressed.

College The book is divided into four main parts, and emphasis is placed on theunity underlying all living things, their diversity in architectural plan,

Classes yet basic similarities and common origins. Most of the chapters are unitsin themselves and the instructor can omit certain chapters if he wishes.

Ready in November-December.

The Maemillan Co., N.Y.

September 28, 1951

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PAPERS IN MICROBIAL GENETICSSelected by Joshua Lederberg

0 The presentation, in a form most available tostudents, of important papers on microbial geneticswhich have heretofore been represented by singlecopies of the original journals. An introductory chap-ter by Professor Lederberg presents a broad survey ofthe subject and an up-to-date bibliography is included.This collection makes it possible for the student ofmicrobial genetics to read and annotate these impor-tant papers at leisure.

Papers included in this volume are by the followingauthors: S. E. Luria and M. Delbruck, (1943); D. E.Lea and C. A. Coulson, (1949); Howard B. New-combe, (1948); Howard B. Newcombe, (1949); M.Demerec, (1948); L. L. Cavalli and G. A. Maccacaro,(1950); Bernard D. Davis, (1950); D. W. Brunerand P. R. Edwards, (1941); P. R. Edwards, L. A.Barnes, and Mary C. Babcock, (1950); D. W. Brunerand P. R. Edwards, (1948); Evelyn M. Witkin,(1947); Robert J. Goodlow, Leonard A. Mika, andWerner Braun, (1950), Joshua Lederberg, (1947);Joshua Lederberg, (1949); C. F. Robinow, (1944);Oswald T. Avery, Colin M. Macleod, and MaclynMcCarty, (1944); F. M. Burnet and Dora Lush,(1936); S. E. Luria, (1945); A. D. Hershey andRaquel Rotman, (1949); S. E. Luria and R. Dulbecco,(1949).

324 pages. Bibliography $3.75

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