Protoplasm a substance which continues—Case of the crystal—Characteristics of generation in the living being—Property of growth—Supposed to be confined to the living being—Fertilization of micro-organisms—Fertilization of crystals—Sterilization of crystalline and living media—Spontaneous generation of crystals—Metastable and labile zones—Glycerine crystals—Possible extinction of a crystalline species—Conclusion. We have not yet exhausted the analogies between a crystal and the living being. The possession of a specific form, the tendency to re-establish it by redisintegration and the existence of a kind of nutrition are not sufficient to constitute complete similarity. It still lacks a fundamental character, that of generation. Chauffard some time ago, in an attack which he made upon the physiological ideas of his day, aptly exhibited this weak point. “Let us disregard,” he said, “those interesting facts relative to the acquisition of a typical form—facts that are common to the mineral world as well as to living beings. It is none the less true that the crystalline type is in no way derived from other pre-existing types, and that nothing in crystallization recalls the actions of ascendants and the laws of heredity.” This gap has since been filled. The work of Gernez, of Violette, of Lecoq de Boisbaudran, the experiments of Ostwald and of Tammann, the observations of Crookes and of Armstrong—all this series of researches, so lucidly summarized by M. Leo Errera in his essays in botanical philosophy, had for their result the establishment of an unsuspected relation between the processes of crystallization and those of generation in animals and plants. _Protoplasm is a Substance which Continues. The Case of the Crystal._—Under present conditions a living being of any kind springs from another living being similar to itself. Its protoplasm is always a continuation of the protoplasm of an ancestor. It is an atavic substance of which we do not see the beginning; we only see it continue. The anatomical element comes from a preceding anatomical element, and the higher animal itself comes from a pre-existing cell of the material organism, the ovum. The ladder of filiation reaches back indefinitely into the past. We shall see that there is something analogous to this in certain crystals. They are born of a preceding individual; they may be considered as the posterity of the antecedent crystal. If we speak of the matter of a crystal as the matter of a living being is spoken of, in cases of this kind we would say that the crystalline substance is an atavic substance of which we see only the continuation, as in the case of protoplasm. _Characters of Generation in the Living Being._—Growth of the living substance, and consequently of the being itself, is the fundamental law of vitality. Generation is the necessary consequence of growth (p. 210).