Page:Popular Science Monthly Volume 48.djvu/787

Rh and the nature of their authority, Nursery Ethics shows very clearly what few parents evidently realize—that the only foundation for parental authority is the furtherance of childish welfare. This is the strict limit. Any further usurpation of authority is simple tyranny. Obedience to persons is also shown to be without moral sanction. But obedience to conditions imposed by events is a large part of the discipline of life. This is the sort of obedience we should teach our children, and with what graciousness we can teach it if we ourselves yield the same obedience! Above all, there should be no conflict of authority. No one detects this sooner than a child, or sooner takes advantage of it. The deepest moral lesson of the nursery comes, as elsewhere, from a recognition of the law of cause and effect. By associating natural results with action, and by adjusting punishments on the same ground, parents may early begin that judicious abdication of authority which is finally to lead to self-government and the evolution of truly moral beings. It is a point of profound wisdom to let this abdication keep always a step in advance of the child's demand for freedom. The chapters on special problems in nursery management deserve no less careful reading. Mrs. Winterburn's book contains much to commend. We believe that every word of it is true. In style and outward dress it is also attractive. If the ethical principles which it so clearly develops could but find an application in the nurseries of America, the chief work of education would be accomplished at home, and the subsequent problems of school and college would be infinitely easier than they are at present. We wish the little book a most successful mission.

Since the general adoption of embryology and histology as a part of the regular medical curriculum, there has been a large accession of works on this subject to our literature—more, it almost seems, than the demand justifies. Many of them are translations, and a very large proportion are not at all suited to the elementary student. A certain amount of confusion is inevitable, because of the unsettled state of the subject, but the chief difficulty has been the lack of an impartial treatment—each author being interested in upholding one of the many theories, and subordinating everything else to this end. Dr. Hertwig's book is fairly free from this fault, and seems to have been carefully arranged with reference to the student's needs. As the title indicates, it deals with cell physiology as well as anatomy. The book consists of nine chapters, with numerous subdivisions under each. Chapter I gives a general historical review of the cell theory, the protoplasmic theory, and the literature of the subject. The Chemico-physical and Morphological Properties of the Cell is the title of Chapter II. In the third, fourth, and fifth chapters the vital properties of the cell are discussed. These are followed by two chapters on The Vital Phenomena of the Cell. The title of Chapter VIII is Metabolic Changes occurring between Protoplasm, Nucleus, and Cell Products, and Chapter IX closes the book with a discussion of the cell as the elementary germ of an organism, embracing theories of heredity. The translation is well done despite the difficulties, which must have been considerable, as the editor says, in finding English equivalents for many of the German words. A good feature is the bibliography which is given after each chapter, thus enabling the student to readily follow out more in detail any special point which he may be curious about. The book is fairly well illustrated.

The last ten years have been marked, in botanical study, by numerous investigations upon the Archegoniates, as the ferns and mosses are collectively called from the peculiar character and resemblance of the organ in them corresponding with the pistil, and by the extension of our knowledge to many forms which were hitherto but very imperfectly known. But while the collected results of the earlier investigations prompted by Hofmeister's work have appeared for the most part only in test-books, where limitations of space prevented full justice being done to them, those of the later researches have only begun to find their way into the text-books. The author, who is Professor