It is a somewhat surprising fact that among educated people of scientific training there prevails generally the greatest ignorance as to some of the most important problems of biology. We refer to those problems connected with the structure and functions of the animal and plant cell. Men who can understand and appreciate recent discoveries in astronomy, physics, chemistry and geology are usually wholly lost in cytology. In fact, in general writing or speech it is not safe to use this name without at once defining it, since it is commonly supposed to be a mispronunciation or a stupid misspelling of ‘psychology,’ while to most people _nuclei_, _chromosomes_, _centrosomes_ and _mitotic spindles_ are words without meaning, signifying nothing. The reason for this is twofold: First, cytology is one of the newest of the biological sciences and it has but recently found its way into college curricula, and second, there have been few text-books or general works on this subject to which an intelligent layman could turn for information. And yet, in spite of this fact, there are few fields of scientific work possessing more general interest than that of cytology. At the present day the greatest problems of biology are centered in the cell. Assimilation, growth, metabolism, reproduction, differentiation, inheritance and variation--these are at bottom cellular phenomena, the result of the structure and functions of cells. It is not surprising, therefore, that “all the searchlights of science have been turned upon the cell,” and that cell studies during the past ten years have received an amount of attention which is comparable only to that devoted to evolution under the stimulus of Darwin’s work. Professor Wilson’s book on the cell,[F] the second edition of which has just appeared, is a work of more than ordinary interest, not only to the biologist, but to all persons who are interested in the general advance of science. Although there are several other good text-books of cytology which have appeared during the past five or six years, Professor Wilson’s book, in thoroughness of treatment, in philosophical insight, in clearness and forcefulness of style and in wealth and beauty of illustrations, easily surpasses them all. [F] The Cell in Development and Inheritance. Edmund B. Wilson. Second Edition Revised and Enlarged. Columbia University Biological Series IV. New York and London, The Macmillan Co., 1900. Pp. xxi, 483 with 194 Figures in the Text. $3.50