other agents than selection that made for modification and descent. And so my theory, perhaps, wears quite through and should go to the rag-bag. The latest conspicuous exposition of the English neo-Darwinian point of view is that embodied in Professor Poulton's "Essays on Evolution" (1908, Oxford). Not that the essays themselves are "latest," for their various dates cover the decade between 1896 and 1906, but they are put out now, with revisions and some additions, as the expression of the distinguished author's present point of view. This is clearly and strongly that of a neo-Darwinian, a thoroughgoing selectionist. The most important and interesting parts of the book are certainly those in which the author exposes the facts and theories of insect mimicry and uses them for argument. These facts and theories are not only the field in which Professor Poulton is especially at home-a field, indeed, which he practically owns -but are also the field in which lie some of the most potent testimony for the deification of selection. Weismann and other neo-Darwinians have never overlooked the stumbling block to Lamarckians and orthogenesists that protective resemblance, warning colors and mimicry constitute, but Professor Poulton with his immense resources of personal knowledge in this field makes to the same end, far more effective use of the facts. The least pleasing and, for that matter, least profitable part of the book to its readers is the polemic introduction, far too bitter and personal, discussing "mutation, Mendelism and natural selection." It mars the book. The essays cover a wide range of subjects: "The age of the earth"; "the definition of species"; "Huxley and selection," in which is maintained the surprising thesis that the great champion of Darwin "was at no time a convinced believer in the theory he protected"; "a remarkable anticipation of modern views on evolution," in which Weismann's arguments against the inheritance of acquired characters are shown to have been in rather full measure advanced by James Cowles Prichard, the English anthropologist, in 1826; "theories of heredity," "theories of evolution," and, most extensively and importantly, the facts and theories of insect mimicry. The exposition of these in the last three chapters and special index, is not only most fascinating and stimulating reading but it will serve until we can have the author's promised more extended treatment in a future book as the latest authoritative exposition of the subject. The book is completed by an amazing analytical index of eighty-three pages, one sixth of the whole book. No reviewer will ever be able to taunt Professor Poulton with that too familiar, "we regret to note the insufficiency of the index." Finally an entomologist may be pardoned for "pointing with pride," in connection with this book to the splendid work for evolution and general biology that the insects have achieved, in the tireless and skillful hands of Professor Poulton. They have painted a wonderful picture in colors of the possibilities of adaptation and the marvelous capacity of selection or some other factor. For the moment selection has all the best of the presumption, but this may depend in considerable measure on its great good fortune in the strength of its champion. There is certainly no gainsaying this strength. Professor Poluton, entrenched in his special field of insect bionomics, is perhaps the most serious antagonist that the neo-Lamarckians have to face. Of somewhat different point of view, and wholly different type, is the other book of Darwinian upholding, which I have at the moment under my eyes. In 1899 Ludwig Plate of the Berlin Landwirthschaftliche Hochschule delivered an address at the meeting of the Deutsche Zoologische Gesellschaft in Hamburg, which was printed in the proceedings of the society under the title "Uber die Bedeutung des Darwin'schen Selectionsprinzips." This address both as spoken and printed attracted. much attention and the demand for it induced Professor Plate to expand and reprint it in book form in 1903. The admirable comprehensiveness of the discussion in the new form still further increased the interest and demand, as a result of which we have now a revised and still more expanded third edition of nearly 500 pages (twice the size of the second edition) under the title: "Selectionsprinzip und Probleme der Artbildung," with the subtitle "Ein Handbuch des Darwinismus" (1908, Engelmann, Leipzig). made a professor of zoology in the University of Berlin as well as in the Landwirthschaftliche Hochschule. The author in the meantime has been Plate is an able friend and defender of selection, but his point of view is not that of Poulton. The Englishman holds rigidly to the neo-Darwinian anti-Lamarckism; the German takes the real standpoint of Darwin, he calls on the inheritance of acquired characters to aid selection in its evolutionary task. He fights Weismanism in almost all of its aspects: panmixia, germinal selection, Allmacht of selection. He resists also any serious encroaching of the mutation theory in the province of species-forming and adaptation. His detailed account and reasoned criticism of De Vries's famous theory are admirable. Isolation, especially those forms of it which may be classified under the general head of "Biologic isolation," is treated in extenso. In this connection Plate opposes those statements of Wagner and D. S. Jordan, which claim that new species do not arise, or do so only very rarely, in the same geographic range. He refers to the hundred Gammarus species in Lake Baikal, the numerous Cladoceran species of Bythotrephes in the Caspian Sea, and the eighty or more chromid kinds in Lake Tanganyika, as examples of nearly related forms that have long inhabited the same limited region and yet among which evolution has steadily gone forward. He discusses the old question of the inheritance of acquired characters in a new way, and those pages in which he explains and justifies his admission of the logical necessity of such an inheritance to explain certain types of adaptation constitute one of the most important parts of the book. His treatment of the Darwinian theory of sexual selection and candid admission of its weaknesses is another admirable instance of the broad-mindedness of this Darwinian champion. Finally his account of the objections to selection and their refutation or recognition as partly valid is simply complete, as is his consideration of the species-forming theories auxiliary to selection. But this fugue of praise grows monotonous, and yet it is hard to introduce any new measure. Perhaps the sparse scattering of pictures may be criticized as being far too meager if illustration was really needed, and easy reading of the text is a little interfered with by the introduction of date and page references into the lines; but these are trifles. The book is excellent arranged both for logical sequence of presentation and for easy reference to any particular phase or topic of the wide subject treated. Professor Plate's acquaintanceship with the active work now going on along the various lines of evolution study and with the literature of the whole subject is manifestly nearly exhaustive. It is especially pleasant to note his generous recognition of American work. PARIS, March, 1909. V. L. K. Eighth Yearbook of the National Society for the Scientific Study of Education T By CHARLES RICHMOND HENDERSON HIS study, which was made at the request of the Executive Committee of the Society, and published after their critical examination, and upon the approval of three medical advisors who have read it, is divided into two parts. The first part is chiefly medical and economic, and seeks to prove the necessity for social control of some kind. Medical authorities are cited to show the nature and prevalence of venereal diseases, and of the physical, economic, and moral loss due to the abuses of sexual life. The various methods of police and administrative control in Europe and America are described and critically discussed. The fundamental cause of the evil is found to lie too deep in nature, habit, ignorance, and social neglect to be reached by merely external police measures. This argument demonstrates the necessity for education with reference to sex-the theme of the second part of the work. In this part is found a careful discussion of educational aims, the scope of educational activities, the co-operat ing agencies in education, the care of infancy, personal hygiene and training, the influence of ideal interests, the principles of formal instruction in relation to sex -its necessity, difficulties, and methods. The distinctive needs of childhood, adolescence, and maturity are treated with care, and the possible modes of instruction in the schools of various grades are presented. The duties of normal schools, of the religious organizations, and of parents, in view of the situation, are set in the light of the facts. In the appendix is printed a valuable paper by Dr. Helen Putnam, president of the American Academy of Medicine, and also translations of important recent discussions of German teachers. The author is president of the Chicago Society of Social Hygiene, and associate member of the American Academy of Medicine, and a Professor of Sociology in the University of Chicago. Part I, 75 pages, 8vo, paper; net 75 cents, postpaid 78 cents. Part II, 100 pages; net 75 cents, postpaid 80 cents. ADDRESS DEPT. 62 THE UNIVERSITY OF CHICAGO PRESS CHICAGO NEW YORK |
