Inanimate bodies, when placed under favourable circumstances, last for an indefinite time, neither taking nor giving anything to the surrounding world; organised beings, under whatever conditions they are placed, only last for a fixed period of time, and, during this existence, undergo every moment losses of substance which they repair by means of materials taken from without. Inanimate bodies, even when they assume the fixed and definite form of crystals, are formed independently of all other bodies resembling them; they have from their commencement fixed forms, and increase simply by superposition of new layers. Every organised being is connected either directly or indirectly with a similar being, in the interior of which it first appeared in the form of a germ, then grew and acquired its definite form by intussusception. In other words, filiation, nutrition, birth and death, are so many characteristics of the organised being, of which no trace is found in inanimate bodies. I agree with Pallas in making inanimate bodies compose the Inorganic Empire, and organised beings the Organic Empire. I must here make an observation, the importance of which will be easily understood. The existence of the two groups which have been recognised by the good sense of the general public as well as by the science of Pallas, is a fact absolutely independent of all hypothesis. Whatever explanation we may propose to account for the differential phenomena which distinguish them, these phenomena will not the less exist; the inanimate body will never be an organised being. To attempt, under any pretext whatever, to reconcile or confound these two kinds of objects with each other, is to go in direct opposition to all the progress made for more than a century, and especially during the last few years, in physics, chemistry and physiology. It is inexplicable to me that some men, whose merits I otherwise acknowledge, should have recently again compared crystals to the simplest living forms, to the sarcodic organisms, as they were called by Dujardin, who discovered them, and was the first to give a comprehensive theory of them from minute observations. A change of name is useless; the things remain the same, and protoplasm has the same properties as sarcode. The animals, whose entire substance they seem to form, have not altered their nature; whether monera or amœbæ, these forms are the antipodes of the crystal from every point of view.