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GENERAL CYTOLOGY

by DeRobertis, Nowinski and SaezThis dynamic book of modern cytology stressesmorphological, physiological and genetic aspectsof the subject. It goes further than mere descrip-tions of physiological changes and seeks to ex-plain these changes in the inner physicochemicalmetabolic processes of protoplasm. On the basisof changes in nuclear structures, the authors at-tempt to interpret the phenomena of heredity,sex, variation, mutation and evolution of plantsand animals.

The authors employ the methods of physics,chemistry and biochemistry to explore the ultra-structure of the cell and to interpret the natureof intracellular processes and the functional sig-

nificance of cellular structure. The text openswith an introduction to the organization of livingmatter. The structure, morphological and cyto-chemical organization of the cell are fully de-scribed. Submicroscopic organization is discussed,and interesting accounts given of the significanceof cytoplasmic organoids. Other important topicsare: molecular structure of plasma membrane,cell permeability, chromosomes and cell division,cellular activity, composition of the nucleus, anddeath of the cell.

Many references are given at the end of eachchapter. Among the illustrations are some of thefinest electron micrographs ever published.

By E. D. P. DEROBERTIS, M.D., Head of the Department of Cell Ultrastructure, Institute for the Investigation of BiologicalSciences, Montevideo; W. W. NoWINSKI, Ph.D., Associate Professor of Biochemistry, University of Texas Medical School,Galveston; and FRANcIscO A. SAEZ, Ph.D., Head of the Department of Cytogenetics, Institute for the Investigation of Bio-logical Sciences, Montevideo. 456 pages, 6A4" x 9'4", with 162 illustrations. $7.75. Second Edition!

EVOLUTION

by DodsonThis strictly scientific book presents today's un-derstanding of organic evolution based on paleon-tology and genetics. It is sound and comprehen-sive, yet written in a clear and understandingstyle for the undergraduate.

The author has woven into a solid framework asummary of traditional viewpoints on evolutionwith a synthesis of the newer viewpoints. All in-terpretations are in strict accord with currentbiological concepts. In keeping with the ele-mentary nature of this presentation, many excel-lent line drawings have been included completewith clearly labeled identifications.

This book is divided into five major sections.Part I, A Definition of Evolution, summarizes the

contents of traditional books on evolution. PartII, Phylogeny, deals with the evolution of highercategories and attempts to trace the main linesof evolution in the plant and animal kingdoms,including the probable lineage of man. Part III,The Origin of Variation, discusses the mode oforigin of those hereditary variations which formthe necessary basis for the action of natural se-lection. Part IV, The Origin Of Species, is con-cerned with the development of discontinuitieswithin a series of varying organisms giving riseto formation of species and higher categories. Thefinal section, Retrospect and Prospect, sum-marizes briefly what has gone before and quotessome predictions for the future of the organicworld.

By EDWARD 0. DODSON, Associate Professor of Biology, University of Notre Dame. 419 pages, 6" x 9Y4", with 101 illustrations.$5.00.

W. B. SAUNDERS COMPANYWest Washington Square Philadelphia 5

SCIENCE is published weekly by the AAAS, 1515 Massachusetts Ave., NW, Washington 5, D.C. Entered at the Lancaster, Pa., Post Office as second classmatter under the act of 3 March 1879. Annual subscriptions: $7.50; foreign postage, $1; Canadian postage, 50.

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SCIENCE, VOL. 122

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812

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814 SCIENCE, VOL. 122