Lamarck, the Founder of Evolution Part 15

What he says in the next two chapters as to the "o.r.g.a.s.me" and irritability excited by the before-mentioned exciting cause may be regarded as a crude foreshadowing of the primary properties of protoplasm, now regarded as the physical basis of life--_i.e._, contractility, irritability, and metabolism. In Chapter VI. Lamarck discusses direct or spontaneous generation in the same way as in 1802.

In the following paragraph we have foreshadowed the characteristic qualities of the primeval protoplasmic matter fitted to receive the first traces of organization and life:

"Every ma.s.s of substance h.o.m.ogeneous in appearance, of a gelatinous or mucilaginous consistence, whose parts, coherent among themselves, will be in the state nearest fluidity, but will have only a consistence sufficient to const.i.tute containing parts, will be the body most fitted to receive the first traces of organization and life."

In the third part of the _Philosophie zoologique_ Lamarck considers the physical causes of feeling--_i.e._, those which form the productive force of actions, and those giving rise to intelligent acts. After describing the nervous system and its functions, he discusses the nervous fluid. His physiological views are based on those of Richerand's _Physiologie_, which he at times quotes.

Lamarck's thoughts on the nature of the nervous fluid (_Recherches sur le fluide nerveux_) are curious and ill.u.s.trative of the gropings after the truth of his age.

He claims that the supposed nervous fluid has much a.n.a.logy to the electric, that it is the _feu ethere_ "animalized by the circ.u.mstances under which it occurs." In his _Recherches sur l'organisation des corps vivans_ (1802) he states that, as the result of changes continually undergone by the princ.i.p.al fluids of an animal, there is continually set free in a state of _feu fixe_ a special fluid, which at the instant of its disengagement occurs in the expansive state of the caloric, then becomes gradually rarefied, and insensibly arrives at the state of an extremely subtile fluid which then pa.s.ses along the smallest nervous ramifications in the substance of the nerve, which is a very good conductor for it. On its side the brain sends back the subtile fluid in question along the nerves to the different organs.

In the same work (1802) Lamarck defines thought as a physical act taking place in the brain. "This act of thinking gives rise to different displacements of the subtile nervous fluid and to different acc.u.mulations of this fluid in the parts of the brain where the ideas have been traced." There result from the flow of the fluid on the conserved impressions of ideas, special movements which portions of this fluid acquire with each impression, which give rise to compounds by their union producing new impressions on the delicate organ which receives them, and which const.i.tute abstract ideas of all kinds, also the different acts of thought.

All the acts which const.i.tute thought are the comparisons of ideas, both simple and complex, and the results of these comparisons are judgments.

He then discusses the influence of the nervous fluid on the muscles, and also its influence considered as the cause of feeling (_sentiment_).

Finally he concludes that _feu fixe_, caloric, the nervous fluid, and the electric fluid "are only one and the same substance occurring in different states."

FOOTNOTES:

[107] Charles Bonnet (1720-1793), a Swiss naturalist, is famous for his work on Aphides and their parthenogenetic generation, on the mode of reproduction in the Polyzoa, and on the respiration of insects. After the age of thirty-four, when his eyesight became impaired, he began his premature speculations, which did not add to his reputation. Judging, however, by an extract from his writings by D'Archiac (_Introduction a l'etude de la Paleontologie stratigraphique_, ii., p. 49), he had sound ideas on the theory of descent, claiming that "la diversite et la mult.i.tude des conjunctions, peut-etre meme la diversite des climats et des nourritures, ont donne naissance a de nouvelles especes ou a des individus intermediaires" (_Oeuvres d'Hist. nat. et de Philosophie_, in-8vo, p. 230, 1779).

[108] See his remark: "_On a dit avec raison que tout ce qui a vie provient d'un auf_" (_Memoires de Physique_, etc., 1797, p. 272). He appears, however, to have made the simplest organisms exceptions to this doctrine.

[109] _Elementa physiologiae corporis humani_, iv. Lausanne, 1762.

[110] _Theoria generationis_, 1774.

[111] _Memoires de Physique_, (1797), p. 250.

[112] _Memoires de Physique_, etc. (1797), p. 272.

[113] Huxley's "Evolution in Biology" (_Darwiniana_, p. 192), where be quotes from Bonnet's statements, which "bear no small resemblance to what is understood by evolution at the present day."

[114] Buffon did not accept Bonnet's theory of preexistent germs, but he a.s.sumed the existence of "_germes acc.u.mules_" which reproduced parts or organs, and for the production of organisms he imagined "_molecules organiques_." Reaumur had previously (1712) conjectured that there were "_germes caches et acc.u.mules_" to account for the regeneration of the limbs of the crayfish. The ideas of Bonnet on germs are stated in his _Memoires sur les Salamandres_ (1777-78-80) and in his _Considerations sur les corps organises_ (1762.)

[115] _Memoires de Physique_, etc., pp. 318, 319, 324-359. Yet the idea of a sort of continuity between the inorganic and the organic world is expressed by Verworn.

[116] _General Physiology_ (English trans., 1899, p. 17). In France vitalism was founded by Bordeu (1722-1766), developed further by Barthez (1734-1806) and Chaussier (1746-1828), and formulated most distinctly by Louis Dumas (1765-1813). Later vitalists gave it a thoroughly mystical aspect, distinguishing several varieties, such as the _nisus formativus_ or formative effort, to explain the forms of organisms, accounting for the fact that from the egg of a bird, a bird and no other species always develops (_l. c._, p. 18).

[117] _Recherches sur l'organisation des corps vivans_ (1802), p. 70.

The same view was expressed in _Memoires de physique_ (1797), pp. 254-257, 386.

[118] Here might be quoted for comparison other famous definitions of life:

"Life is the sum of the functions by which death is resisted."--Bichat.

"Life is the result of organization."--(?)

"Life is the principle of individuation."--Coleridge ex. Sch.e.l.ling.

"Life is the twofold internal movement of composition and decomposition, at once general and continuous."--De Blainville, who wisely added that there are "two fundamental and correlative conditions inseparable from the living being--an organism and a medium."

"Life is the continuous adjustment of internal relations to external relations."--Herbert Spencer.

CHAPTER XI

LAMARCK AS A BOTANIST

During the century preceding the time of Lamarck, botany had not flourished in France with the vigor shown in other countries. Lamarck himself frankly stated in his address to the Committee of Public Instruction of the National Convention that the study of plants had been for a century neglected by Frenchmen, and that the great progress which it had made during this time was almost entirely due to foreigners.

"I am free to say that since the distinguished Tournefort the French have remained to some extent inactive in this direction; they have produced almost nothing, unless we except some fragmentary mediocre or unimportant works. On the other hand, Linne in Sweden, Dilwillen in England, Haller in Switzerland, Jacquin in Austria, etc., have immortalized themselves by their own works, vastly extending the limit of our knowledge in this interesting part of natural history."

What led young Lamarck to take up botanical studies, his botanical rambles about Paris, and his longer journeys in different parts of France and in other countries, his six years of unremitting labor on his _Flore Francaise_, and the immediate fame it brought him, culminating in his election as a member of the French Academy, have been already recounted.

Lamarck was thirty-four when his _Flore Francaise_ appeared. It was not preceded, as in the case of most botanical works, by any preliminary papers containing descriptions of new or unknown species, and the three stout octavo volumes appeared together at the same date.

The first volume opens with a report on the work made by MM. Duhamel and Guettard. Then follows the _Discours Preliminaire_, comprising over a hundred pages, while the main body of the work opens with the _Principes elementaires de Botanique_, occupying 223 pages. The work was a general elementary botany and written in French. Before this time botanists had departed from the artificial system of Linne, though it was convenient for amateurs in naming their plants. Jussieu had proposed his system of natural families, founded on a scientific basis, but naturally more difficult for the use of beginners. To obviate the matter Lamarck conceived and proposed the dichotomic method for the easy determination of species. No new species were described, and the work, written in the vernacular, was simply a guide to the indigenous plants of France, beginning with the cryptogams and ending with the flowering plants. A second edition appeared in 1780, and a third, edited and remodelled by A. P. De Candolle, and forming six volumes, appeared in 1805-1815. This was until within a comparatively few years the standard French botany.

Soon after the publication of his _Flore Francaise_ he projected two other works which gave him a still higher position among botanists. His _Dictionnaire de Botanique_ was published in 1783-1817, forming eight volumes and five supplementary ones. The first two and part of the third volume were written by Lamarck, the remainder by other botanists, who completed it after Lamarck had abandoned botanical studies and taken up his zoological work. His second great undertaking was _L'Ill.u.s.tration des Genres_ (1791-1800), with a supplement by Poiret (1823).

Cuvier speaks thus of these works:

"_L'Ill.u.s.tration des Genres_ is a work especially fitted to enable one to acquire readily an almost complete idea of this beautiful science. The precision of the descriptions and of the definitions of Linnaeus is maintained, as in the inst.i.tutions of Tournefort, with figures adapted to give body to these abstractions, and to appeal both to the eye and to the mind, and not only are the flowers and fruits represented, but often the entire plant. More than two thousand genera are thus made available for study in a thousand plates in quarto, and at the same time the abridged characters of a vast number of species are given.

"The _Dictionnaire_ contains more details of the history with careful descriptions, critical researches on their synonymy, and many interesting observations on their uses or on special points of their organizations. The matter is not all original in either of the works, far from it, but the choice of figures is skilfully made, the descriptions are drawn from the best authors, and there are a large number which relate to species and also some genera previously unknown."

Lamarck himself says that after the publication of his _Flore Francaise_, his zeal for work increasing, and after travelling by order of the government in different parts of Europe, he undertook on a vast scale a general work on botany.

"This work comprised two distinct features. In the first (_Le Dictionnaire_), which made a part of the new encyclopedia, the citizen Lamarck treats of philosophical botany, also giving the complete description of all the genera and species known. An immense work from the labor it cost, and truly original in its execution....

The second treatise, ent.i.tled _Ill.u.s.tration des Genres_, presents in the order of the s.e.xual system the figures and the details of all the genera known in botany, and with a concise exposition of the generic characters and of the species known. This work, unique of its kind, already contains six hundred plates executed by the best artists, and will comprise nine hundred. Also for more than ten years the citizen Lamarck has employed in Paris a great number of artists. Moreover, he has kept running three separate presses for different works, all relating to natural history."

Cuvier in his _eloge_ also adds:

"It is astonishing that M. de Lamarck, who hitherto had been studying botany as an amateur, was able so rapidly to qualify himself to produce so extensive a work, in which the rarest plants were described. It is because, from the moment he undertook it, with all the enthusiasm of his nature, he collected them from the gardens and examined them in all the available herbaria; pa.s.sing the days at the houses of the botanists he knew, but chiefly at the home of M.

de Jussieu, in that home where for more than a century a scientific hospitality welcomed with equal kindness every one who was interested in the delightful study of botany. When any one reached Paris with plants he might be sure that the first one who should visit him would be M. de Lamarck; this eager interest was the means of his receiving one of the most valuable presents he could have desired. The celebrated traveller Sonnerat, having returned in 1781 for the second time from the Indies, with very rich collections of natural history, imagined that every one who cultivated this science would flock to him; it was not at Pondichery or in the Moluccas that he had conceived an idea of the vortex which too often in this capital draws the savants as well as men of the world; no one came but M. de Lamarck, and Sonnerat, in his chagrin, gave him the magnificent collection of plants which he had brought. He profited also by that of Commerson, and by those which had been acc.u.mulated by M. de Jussieu, and which were generously opened to him."

These works were evidently planned and carried out on a broad and comprehensive scale, with originality of treatment, and they were most useful and widely used. Lamarck's original special botanical papers were numerous. They were mostly descriptive of new species and genera, but some were much broader in scope and were published over a period of ten years, from 1784 to 1794, and appeared in the _Journal d'Histoire naturelle_, which he founded, and in the _Memoires_ of the Academy of Sciences.

He discussed the shape or aspect of the plants characteristic of certain countries, while his last botanical effort was on the sensibility of plants (1798).

Although not in the front rank of botanists, compared with Linne, Jussieu, De Candolle, and others, yet during the twenty-six years of his botanical career it may safely be said that Lamarck gave an immense impetus to botany in France, and fully earned the t.i.tle of "the French Linne."

Lamarck not only described a number of genera and species of plants, but he attempted a general cla.s.sification, as Cleland states: