Our release from this service is of course gradual. As the demands made upon us by the government are lessened from month to month, however, we are enabled to increase deliveries to our other patrons. Write for Balopticon Catalog, with price list of our revised line, and inform us regarding your requirements. Bausch & Lomb Optical @. 522 ST. PAUL STREET, ROCHESTER, N. Y. New York Washington Chicago San Francisco Leading American Makers of Photographic Lenses, Microscopes, Projection Apparatus (Balopti- The Action of Ultraviolet Light on Certain Bac- .10 The above titles represent University of California Publications in Agricultural Science, Botany, American Archaeology and Ethnology, Pathology, and Zoology. Other series published by the University of California include: Entomology, Geography, Geology, Physiology, and Psychology. Complete Lists of Titles and Prices will be sent Memoirs of the Wistar Institute of Anatomy and THE RAT Data and Reference Tables. 278 Pages. 89 Tables. The Wistar Institute Philadelphia, Pa. OPTIC PROJECTION TWO BOOKS BY Old theories under the searchlight of modern scientific experiment. This is a book for the synthetic mind which compares and analyzes results obtained by the direct experiment of the specialist. EUGENIO RIGNANO Rignano's studies lie in the borderland between physical chemistry and biology, and indicate a possible road to the understanding of the physical nature of living substance as distinguished from the non-living substance. THE OPEN COURT PUBLISHING CO., 122 South Michigan Avenue, Chicago, III. APPLIED EUGENICS By Captain PAUL POPENOE, Formerly Editor Cloth, Crown 8vo, xii+459 pages, with 46 illustrations. $2.10 "This book is written on the general assumption that human beings differ physically, mentally and morally, and that the basis, at least, of these differences is due to heredity. Environment may affect the individual, but not the qualities passed on to the next generation. Even vices have less influence in this direction than is generally believed. Natural selection is still working among men and determining survival. The first six chapters furnish the evidence for these assumptions. Several chapters are devoted to the history of the eugenics movement, the evidence as to the existence of dysgenic classes and the means of lessening their reproduction, and the desirability and possibility of increasing the marriage and birth rates of the superior groups. Here the authors have spoken with restraint and avoided extreme positions. They favor segregation of the unfit rather than surgery, and sharply criticise most of the existing legislation. It is a happy suggestion that society should condemn mismating, not the divorce of the mismated. The authors have gathered an enormous amount of evidence which will repay careful consideration by social workers, lawyers, teachers, ministers, and all who are interested in social problems. The style is clear and condensed. The volume is well illustrated and will prove to be one of the most useful books in the field."-Professor Carl Kelsey of the University of Pennsylvania in The Survey, issue of January 25th, 1919. "The book is valuable as the first serious attempt to cover so large a field . . ... It is stimulating and thought-provoking, and deserves the widest possible circulation, not only among eugenicists but all persons interested in social progress."-From Eugenical News, January, 1919. PRINCIPLES OF CHEMISTRY JOEL H. HILDEBRAND, Professor of Chemistry in the University Cloth, 12mo, ix+313 pp., Diagrams, $1.75 "The treatment is clear, readable and altogether satisfactory. All teachers of chemistry who are seeking to improve their methods of presentation will find it suggestive and interesting, and if they do not adopt the scheme of instruction for which it is designed, they will probably be influenced by it none the less in their teaching."-The Nation. "The average textbook in chemistry assumes that its order and arrangement will be strictly followed; if it is not, much of its value to the student is lost; if it is, freedom and individuality are threatened. The author of this new text has admirably avoided much of this difficulty by an arrangement of material that conduces to the utmost flexibility; his subject divisions may be used with various forms of descriptive material, and provision has been made for considerable departure from the given order."-Scientific American. "In this work the elements and processes mentioned are in illustration of the laws and principles, rather than a formal study of the elements, their combinations and properties per se. In this, it is interesting to the non-chemist, and could be read by our non-technical people with interest and profit."-General Chemical Bulletin. 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MONOGRAPHS ON EXPERIMENTAL BIOLOGY AND GENERAL PHYSIOLOGY The publishers take much pleasure in announcing a new series of monographs covering the subjects of experimental biology and general physiology. These volumes will be under the general editorship of Jacques Loeb, T. H. Morgan, and W. J. V. Osterhout. NOW READY The Elementary Nervous System By G. H. PARKER, Sc.D., Professor of Zoology, Harvard University. The dependence of human affairs upon the nervous system of man is so absolute that it was inevitable, as soon as this relation was understood, that the activities of the simpler animals should be interpreted as though these creatures were miniature human beings. That such interpretation was carried far beyond its legitimate bounds, even by the scientifically trained, is now admitted on almost all sides, but it is no easy or simple task to ascribe to this movement its proper bounds. That these bounds are vastly more restricted than has usually been supposed is certain. An approach to a clearer understanding of what they are is assured through the application of experimental and quantitative methods to the questions concerned rather than by a continuation of the older more purely observational procedure. It is from this standpoint that an attempt has been made in this volume to portray the elementary nervous system as it exists in the simpler animals and in the simpler parts of the more complex forms. Forced Movements, Tropisms, and Animal Conduct By JACQUES LOEB, M.D., Ph.D., Sc.D., Member of the Rockefeller Institute for Animal conduct is known to many through the romantic tales of popularizers, through the descriptive work of biological observers, or through the attempts of vitalists to show the inadequacy of physical laws for the explanation of life. Since none of these contributions are based upon quantitative experiments, they have led only to speculations, which are generally of an anthropomorphic or of a purely verbalistic character. It is the aim of this monograph to show that the subject of animal conduct can be treated by the quantitative methods of the physicist, and that these methods lead to the forced movements or tropism theory of animal conduct, which has only recently been carried to some degree of completion. IN PREPARATION THE CHROMOSOME THEORY OF HER- INBREEDING AND OUTBREEDING: Their By H. S. PURE LINE INHERITANCE. THE NATURE OF ANIMAL LIFE. By PERMEABILITY AND ELECTRICAL CON- CHEMICAL BASIS OF GROWTH. By T. COORDINATION IN LOCOMOTION. By J. B. LIPPINCOTT COMPANY CHICAGO BOSTON ATLANTA MONTREAL LONDON |