"This is not all; up to the present time the animalized corpuscle we are considering is still only a primitive animalcule because it as yet has no special organ. Let us see then how nature will come to furnish it with any primitive special organ, and what will be the organ that nature will form before any others, and which in the simplest animal is the only one constantly found; this is the alimentary canal, the principal organ of digestion common to all except colpodes, vibrios, proteus (amoeba), volvoces, monads, etc. "This digestive canal is," he says--proceeding with his _à priori_ morphology--"a little different from that of this day, produced by contractions of the body, which are stronger in one part of the body than in another, until a little crease is produced on the surface of the body. This furrow or crease will receive the food. Insensibly this little furrow by the habit of being filled, and by the so frequent use of its pores, will gradually increase in depth; it will soon assume the form of a pouch or of a tubular cavity with porous walls, a blind sac, or with but a single opening. Behold the primitive alimentary canal created by nature, the simplest organ of digestion." In like _à priori_ manner he describes the creation of the faculty of reproduction. The next organ, he says, is that of reproduction due to the regenerative faculty. He describes fission and budding. Finally (p. 122) he says: "Indeed, we perceive that if the first germs of living bodies are all formed in one day in such great abundance and facility under favorable circumstances, they ought to be, nevertheless, by reason of the antiquity of the causes which make them exist, the most ancient organisms in nature." In 1794 he rejected the view once held of a continuous chain of being, the _échelle des êtres_ suggested by Locke and by Leibnitz, and more fully elaborated by Bonnet, from the inorganic to the organic worlds, from minerals to plants, from plants to polyps (our Infusoria), polyps to worms, and so on to the higher animals. He, on the contrary, affirms that nature makes leaps, that there is a wide gap between minerals and living bodies, that everything is not gradated and shaded into each other. One reason for this was possibly his strange view, expressed in 1794, that all brute bodies and inorganic matters, even granite, were not formed at the same epoch but at different times, and were derived from organisms.[115] The mystical doctrine of a vital force was rife in Lamarck's time. The chief starting point of the doctrine was due to Haller, and, as Verworn states, it is a doctrine which has confused all physiology down to the middle of the present century, and even now emerges again here and there in varied form.[116]