BOOK REVIEWS

Book reviewed in this article: B irds , by Gayle Pickwell, Professor of Zoology, at San José State College, San José, California . A L aboratory I ntroduction to A nimal E cology and T axonomy , by Orlando Park, Associate Professor of Zoölogy, Northwestern University ; W. C. Allee, Professor of Zoölogy, University of Chicago; and V. E. Shelford, Professor of Zoölogy, University of Illinois G rowing P lants W ithout S oil . The A.B.C. of Plant Chemiculture (Soilless Chemiculture, Water Culture, Hydroponics, Tank Farming, Sand Culture) Including Plant Growth Hormones and Their Use. By D. R. Matlin, M.A, Professor of Plant Chemicullure, Belmont Evening High School, Los Angeles, Calif . T he P rinciples of H eredity , Second Edition, by Laurence H. Snyder, Sc.D., Professor of Zoology, Ohio State University, Columbus, Ohio T he P hotismi de L umine of M aurolycus , Translated from the Latin into English by Henry Crew, Northwestern University . T he O rigin of C anyons , by Douglas Johnson, Professor of physiography, Columbia University . M odern A gricultural M athematics , a Text Book for Students of Agriculture in High Schools, Vocational Schools and Rural Schools; and a Handy Reference Book for Farmers and Other Workers in the Various Branches of Agriculture. Containing Methods of Calculation for All Types of Agricultural Problems, by Maurice Nadler, Department of Mathematics, Agriculture Division of Newtown High School, Long Island . M athematical M ethods in E ngineering , by Theodore v. Karman, Director of the Guggenheim Aeronautics Laboratory, California Institute of Technology and Maurice A. Biot, Assistant Professor of Mechanics, Columbia University; Honorary Professor, University of Louvain . U seful M athematics W orkbook , by Mary A. Potter, Supervisor of Mathematics, Racine, Wisconsin .