Leçons sur la Cellule Morphologie et Réproduction faites au Collège de France pendant le semestre d'hiver 1893–94

Abstract

THE cell occupies, and has for half a century occupied, so important a position in biological science, that the literature dealing with it and the number of general works called up by this literature has become enormous, and is daily increasing. Nor is this a matter to be wondered at, for the subject is one of supreme importance to the biologist, and contains within its border the very innermost mysteries of life. But in saying this, we do not wish to be understood as giving our adhesion to this or to that modern school of thought with regard to the importance of the cell in organisms. It is sufficient for us to note the fact that, great as has been the influence of the conception of cell on biological investigations in the last fifty years, the chief merit of the founders of the cell-theory lay less in giving us that conception than in fixing attention upon the matter of which the organism is composed. To the cell-theory we owe our conception of the organism as a body composed of protoplasm—the real living matter, and of formed material—the non-living or semi-living framework. The former is the true seat of life, and the latter is produced as a result of its vital activity. This conception has been an analytical tool of the most powerful kind, and has assisted very considerably in the task of unravelling the complexity of structure and function of the parts of organisms. The cell-theory first fixed our attention upon protoplasm, and upon that most important part of protoplasm the nucleus; and it is to the study of protoplasm and of the nucleus, of their structure, relations, and activities, that the great advances in modern biology are due. This, we repeat, was the great work of the founders of the cell-theory. But they did more than this: they first showed us that the living substance is often arranged in and works through small structural units called cells; and they first gave us the idea that the organism is composed of independent or semi-independent individuals associated together in a colony for the common good. It is this idea, this hypothetical explanation of cellular structure, which constitutes the cell-theory; and it must be clearly borne in mind that the promulgation of this hypothesis was the least important part of the work of the founders of that theory. At the same time it is an undeniable fact that this hypothesis was held, and indeed is held largely at the present day; and that it has had a most important influence upon biological research. Of its value we express no opinion, but we should be wanting in our duty if we did not point out that of late years a slowly increasing number of biologists have cast doubts upon its validity and utility as an explanation of cellular structure, and are content to hold for the present that cellular structure has not received any adequate explanation, or, to use the somewhat vague words of Sachs, is a phenomenon of secondary significance, and merely one of the numerous expressions of the formative forces which reside in all matter, and in the highest degree in organic substance.

Leçons sur la Cellule Morphologie et Réproduction faites au Collège de France pendant le semestre d'hiver 1893–94.

Par Félix Henneguy. Pp. xix + 541. 362 figures. (Paris: Georges Carré, 1896.)