Chapter 4

PROFESSOR OF INVERTEBRATE ZOÖLOGY AT THE MUSEUM

Lamarck's career as a botanist comprised about twenty-five years. We now come to the third stage of his life--Lamarck the zoölogist and evolutionist. He was in his fiftieth year when he assumed the duties of his professorship of the zoölogy of the invertebrate animals; and at a period when many men desire rest and freedom from responsibility, with the vigor of an intellectual giant Lamarck took upon his shoulders new labors in an untrodden field both in pure science and philosophic thought.

It was now the summer of 1793, and on the eve of the Reign of Terror, when Paris, from early in October until the end of the year, was in the deadliest throes of revolution. The dull thud of the guillotine, placed in front of the Tuileries, in the Place de la Revolution, which is now the Place de la Concorde, a little to the east of where the obelisk of Luxor now stands, could almost be heard by the quiet workers in the Museum, for sansculottism in its most aggressive and hideous forms raged not far from the Jardin des Plantes, then just on the border of the densest part of the Paris of the first Revolution. Lavoisier, the founder of modern chemistry, was guillotined some months later. The Abbé Haüy, the founder of crystallography, had been, the year previous, rescued from prison by young Geoffroy St. Hilaire, his neck being barely saved from the gleaming axe. Roland, the friend of science and letters, had been so hunted down that at Rouen, in a moment of despair, on hearing of his wife's death, he thrust his sword-cane through his heart. Madame Roland had been beheaded, as also a cousin of her husband, and we can well imagine that these fateful summer and autumn days were scarcely favorable to scientific enterprises.[32] Still, however, amid the loud alarums of this social tempest, the Museum underwent a new birth which proved not to be untimely. The Minister of the Interior (Garat) invited the professors of the Museum to constitute an assembly to nominate a director and a treasurer, and he begged them to present extracts of their deliberations for him to send to the executive council, "under the supervision of which the National Museum is for the future placed;" though in general the assembly only reported to the Minister matters relating to the expenses, the first annual grant of the Museum being 100,000 livres.

Four days after, June 14th, the assembly met and adopted the name of the establishment in the following terms: _Muséum d'Histoire Naturelle décrété par la Convention Nationale le 10 Juin, 1793_; and at a meeting held on the 9th of July the assembly definitely organized the first bureau, with Daubenton as director, Thouin treasurer, and Desfontaines secretary. Lamarck, as the records show, was present at all these meetings, and at the first one, June 14th, Lamarck and Fourcroy were designated as commissioners for the formation of the Museum library.

All this was done without the aid or presence of Bernardin de Saint-Pierre, the Intendant. The Minister of the Interior, meanwhile, had communicated to him the decision of the National Convention, and invited him to continue his duties up to the moment when the new organization should be established. After remaining in his office until July 9th, he retired from the Museum August 7th following, and finally withdrew to the country at Essones.

The organization of the Museum is the same now as in 1793, having for over a century been the chief biological centre of France, and with its magnificent collections was never more useful in the advancement of science than at this moment.

Let us now look at the composition of the assembly of professors, which formed the Board of Administration of the Museum at the time of his appointment.

The associates of Lamarck and Geoffroy St. Hilaire, who had already been connected with the Royal Garden and Cabinet, were Daubenton, Thouin, Desfontaines, Portal, and Mertrude. The Nestor of the faculty was Daubenton, who was born in 1716. He was the collaborator of Buffon in the first part of his _Histoire Naturelle_, and the author of treatises on the mammals and of papers on the bats and other mammals, also on reptiles, together with embryological and anatomical essays. Thouin, the professor of horticulture, was the veteran gardener and architect of the Jardin des Plantes, and withal a most useful man. He was affable, modest, genial, greatly beloved by his students, a man of high character, and possessing much executive ability. A street near the Jardin was named after him. He was succeeded by Bosc. Desfontaines had the chair of botany, but his attainments as a botanist were mediocre, and his lectures were said to have been tame and uninteresting. Portal taught human anatomy, while Mertrude lectured on vertebrate anatomy; his chair was filled by Cuvier in 1795.

Of this group Lamarck was _facile princeps_, as he combined great sagacity and experience as a systematist with rare intellectual and philosophic traits. For this reason his fame has perhaps outlasted that of his young contemporary, Geoffroy St. Hilaire.

The necessities of the Museum led to the division of the chair of zoölogy, botany being taught by Desfontaines. And now began a new era in the life of Lamarck. After twenty-five years spent in botanical research he was compelled, as there seemed nothing else for him to undertake, to assume charge of the collection of invertebrate animals, and to him was assigned that enormous, chaotic mass of forms then known as molluscs, insects, worms, and microscopic animals. Had he continued to teach botany, we might never have had the Lamarck of biology and biological philosophy. But turned adrift in a world almost unexplored, he faced the task with his old-time bravery and dogged persistence, and at once showed the skill of a master mind in systematic work.

The two new professorships in zoölogy were filled, one by Lamarck, previously known as a botanist, and the other by the young Étienne Geoffroy St. Hilaire, then twenty-two years old, who was at that time a student of Haüy, and in charge of the minerals, besides teaching mineralogy with especial reference to crystallography.

To Geoffroy was assigned the four classes of vertebrates, but in reality he only occupied himself with the mammals and birds. Afterwards Lacépède[33] took charge of the reptiles and fishes. On the other hand, Lamarck's field comprised more than nine-tenths of the animal kingdom. Already the collections of insects, crustacea, worms, molluscs, echinoderms, corals, etc., at the Museum were enormous. At this time France began to send out those exploring expeditions to all parts of the globe which were so numerous and fruitful during the first third of the nineteenth century. The task of arranging and classifying single-handed this enormous mass of material was enough to make a young man quail, and it is a proof of the vigor, innate ability, and breadth of view of the man that in this pioneer work he not only reduced to some order this vast horde of forms, but showed such insight and brought about such radical reforms in zoölogical classification, especially in the foundation and limitation of certain classes, an insight no one before him had evinced. To him and to Latreille much of the value of the _Règne Animal_ of Cuvier, as regards invertebrate classes, is due.

The exact title of the chair held by Lamarck is given in the _État_ of persons attached to the National Museum of Natural History at the date of the 1er messidor, an II. of the Republic (1794), where he is mentioned as follows: "LAMARCK--fifty years old; married for the second time; wife _enceinte_; six children; professor of zoölogy, of insects, of worms, and microscopic animals." His salary, like that of the other professors, was put at 2,868 livres, 6 sous, 8 deniers.[34]

Étienne Geoffroy St. Hilaire[35] has related how the professorship was given to Lamarck.

"The law of 1793 had prescribed that all parts of the natural sciences should be equally taught. The insects, shells, and an infinity of organisms--a portion of creation still almost unknown--remained to be treated in such a course. A desire to comply with the wishes of his colleagues, members of the administration, and without doubt, also, the consciousness of his powers as an investigator, determined M. de Lamarck: this task, so great, and which would tend to lead him into numberless researches; this friendless, unthankful task he accepted--courageous resolution, which has resulted in giving us immense undertakings and great and important works, among which posterity will distinguish and honor forever the work which, entirely finished and collected into seven volumes, is known under the name of _Animaux sans Vertèbres_."

Before his appointment to this chair Lamarck had devoted considerable attention to the study of conchology, and already possessed a rather large collection of shells. His last botanical paper appeared in 1800, but practically his botanical studies were over by 1793.

During the early years of the Revolution, namely, from 1789 to and including 1791, Lamarck published nothing. Whether this was naturally due to the social convulsions and turmoil which raged around the Jardin des Plantes, or to other causes, is not known. In 1792, however, Lamarck and his friends and colleagues, Bruguière, Olivier, and the Abbé Haüy, founded the _Journal d'Histoire Naturelle_, which contains nineteen botanical articles, two on shells, besides one on physics, by Lamarck. These, with many articles by other men of science, illustrated by plates, indicate that during the years of social unrest and upheaval in Paris, and though France was also engaged in foreign wars, the philosophers preserved in some degree, at least, the traditional calm of their profession, and passed their days and nights in absorption in matters biological and physical. In 1801 appeared his _Système des Animaux sans Vertèbres_, preceded by the opening discourse of his lectures on the lower animals, in which his views on the origin of species were first propounded. During the years 1793-1798, or for a period of six years, he published nothing on zoölogy, and during this time only one paper appeared, in 1798, on the influence of the moon on the earth's atmosphere. But as his memoirs on fire and on sound were published in 1798, it is evident that his leisure hours during this period, when not engaged in museum work and the preparation of his lectures, were devoted to meditations on physical and meteorological subjects, and most probably it was towards the end of this period that he brooded over and conceived his views on organic evolution.

It appears that he was led, in the first place, to conchological studies through his warm friendship for a fellow naturalist, and this is one of many proofs of his affectionate, generous nature. The touching story is told by Étienne Geoffroy St. Hilaire.[36]

"It was impossible to assign him a professorship of botany. M. de Lamarck, then forty-nine years old, accepted this change in his scientific studies to take charge of that which everybody had neglected; because it was, indeed, a heavy load, this branch of natural history, where, with so varied relations, everything was to be created. On one group he was a little prepared, but it was by accident; a self-sacrifice to friendship was the cause. For it was both to please his friend Bruguière as well as to penetrate more deeply into the affections of this very reserved naturalist, and also to converse with him in the only language which he wished to hear, which was restricted to conversations on shells, that M. de Lamarck had made some conchological studies. Oh, how, in 1793, did he regret that his friend had gone to Persia! He had wished, he had planned, that he should take the professorship which it was proposed to create. He would at least supply his place; it was in answer to the yearnings of his soul, and this affectionate impulse became a fundamental element in the nature of one of the greatest of zoölogical geniuses of our epoch."

Once settled in his new line of work, Lamarck, the incipient zoölogist, at a period in life when many students of less flexible and energetic natures become either hide-bound and conservative, averse to taking up a different course of study, or actually cease all work and rust out--after a half century of his life had passed, this rare spirit, burning with enthusiasm, charged like some old-time knight or explorer into a new realm and into "fresh fields and pastures new." His spirit, still young and fresh after nearly thirty years of mental toil, so unrequited in material things, felt a new stimulus as he began to investigate the lower animals, so promising a field for discovery.

He said himself:

"That which is the more singular is that the most important phenomena to be considered have been offered to our meditations only since the time when attention has been paid to the animals least perfect, and when researches on the different complications of the organization of these animals have become the principal foundation of their study. It is not less singular to realize that it was almost always from the examination of the smallest objects which nature presents to us, and that of considerations which seem to us the most minute, that we have obtained the most important knowledge to enable us to arrive at the discovery of her laws, and to determine her course."

After a year of preparation he opened his course at the Museum in the spring of 1794. In his introductory lecture, given in 1803, after ten years of work on the lower animals, he addressed his class in these words:

"Indeed it is among those animals which are the most multiplied and numerous in nature, and the most ready to regenerate themselves, that we should seek the most instructive facts bearing on the course of nature, and on the means she has employed in the creation of her innumerable productions. In this case we perceive that, relatively to the animal kingdom, we should chiefly devote our attention to the invertebrate animals, because their enormous multiplicity in nature, the singular diversity of their systems of organization and of their means of multiplication, their increasing simplification, and the extreme fugacity of those which compose the lowest orders of these animals, show us, much better than the higher animals, the true course of nature, and the means which she has used and which she still unceasingly employs to give existence to all the living bodies of which we have knowledge."

During this decade (1793-1803) and the one succeeding, Lamarck's mind grew and expanded. Before 1801, however much he may have brooded over the matter, we have no utterances in print on the transformation theory. His studies on the lower animals, and his general knowledge of the vertebrates derived from the work of his contemporaries and his observations in the Museum and menagerie, gave him a broad grasp of the entire animal kingdom, such as no one before him had. As the result, his comprehensive mind, with its powers of rapid generalization, enabled him to appreciate the series from monad (his _ébauche_) to man, the range of forms from the simple to the complex. Even though not a comparative anatomist like Cuvier, he made use of the latter's discoveries, and could understand and appreciate the gradually increasing complexity of forms; and, unlike Cuvier, realize that they were blood relations, and not separate, piece-meal creations. Animal life, so immeasurably higher than vegetable forms, with its highly complex physiological functions and varied means of reproduction, and the relations of its forms to each other and to the world around, affords facts for evolution which were novel to Lamarck, the descriptive botanist.

In accordance with the rules of the Museum, which required that all the professors should be lodged within the limits of the Jardin, the choice of lodgings being given to the oldest professors, Lamarck, at the time of his appointment, took up his abode in the house now known as the Maison de Buffon, situated on the opposite side of the Jardin des Plantes from the house afterwards inhabited by Cuvier, and in the angle between the Galerie de Zoologie and the Museum library.[37] With little doubt the windows of his study, where his earlier addresses, the _Recherches sur l'Organisation des Corps Vivans_, and the _Philosophie Zoologique_, were probably written, looked out upon what is now the court on the westerly side of the house, that facing the Rue Geoffroy St. Hilaire.

At the time of his entering on his duties as professor of zoölogy, Lamarck was in his fiftieth year. He had married twice and was the father of six children, and without fortune. He married for a third, and afterwards for a fourth time, and in all, seven children were born to him, as in the year (1794) the minute referring to his request for an indemnity states: "Il est chargé de sept enfans dont un est sur les vaisseaux de la République." Another son was an artist, as shown by the records of the Assembly of the Museum for September 23, 1814, when he asked for a chamber in the lodgings of Thouin, for the use of his son, "_peintre_."

Geoffroy St. Hilaire, in 1829, spoke of one of his sons, M. Auguste de Lamarck, as a skilful and highly esteemed engineer of Ponts-et-Chaussées, then advantageously situated.

But man cannot live by scientific researches and philosophic meditations alone. The history of Lamarck's life is painful from beginning to end. With his large family and slender salary he was never free from carking cares and want. On the 30 fructidor, an II. of the Republic, the National Convention voted the sum of 300,000 livres, with which an indemnity was to be paid to citizens eminent in literature and art. Lamarck had sacrificed much time and doubtless some money in the preparation and publication of his works, and he felt that he had a just claim to be placed on the list of those who had been useful to the Republic, and at the same time could give proof of their good citizenship, and of their right to receive such indemnity or appropriation.

Accordingly, in 1795 he sent in a letter, which possesses much autobiographical interest, to the Committee of Public Instruction, in which he says:

"During the twenty-six years that he has lived in Paris the citizen Lamarck has unceasingly devoted himself to the study of natural history, and particularly botany. He has done it successfully, for it is fifteen years since he published under the title of _Flore Française_ the history and description of the plants of France, with the mention of their properties and of their usefulness in the arts; a work printed at the expense of the government, well received by the public, and which now is much sought after and very rare." He then describes his second great botanical undertaking, the _Encyclopædia and Illustration of Genera_, with nine hundred plates. He states that for ten years past he has kept busy "a great number of Parisian artists, three printing presses for different works, besides delivering a course of lectures."

The petition was granted. At about this period a pension of twelve hundred francs from the Academy of Sciences, and which had increased to three thousand francs, had ceased eighteen months previously to be paid to him. But at the time (an II.) Lamarck was "chargé de sept enfans," and this appropriation was a most welcome addition to his small salary.

The next year (an III.) he again applied for a similar allowance from the funds providing an indemnity for men of letters and artists "whose talents are useful to the Republic." Again referring to the _Flore Française_, and his desire to prepare a second edition of it, and his other works and travels in the interest of botanical science, he says:

"If I had been less overburdened by needs of all kinds for some years, and especially since the suppression of my pension from the aforesaid Academy of Sciences, I should prepare the second edition of this useful work; and this would be, without doubt, indeed, the opportunity of making a new present to my country.

"Since my return to France I have worked on the completion of my great botanical enterprises, and indeed for about ten years past my works have obliged me to keep in constant activity a great number of artists, such as draughtsmen, engravers, and printers. But these important works that I have begun, and have in a well-advanced state, have been in spite of all my efforts suspended and practically abandoned for the last ten years. The loss of my pension from the Academy of Sciences and the enormous increase in the price of articles of subsistence have placed me, with my numerous family, in a state of distress which leaves me neither the time nor the freedom from care to cultivate science in a fruitful way."

Lamarck's collection of shells, the accumulation of nearly thirty years,[38] was purchased by the government at the price of five thousand livres. This sum was used by him to balance the price of a national estate for which he had contracted by virtue of the law of 28 ventôse de l'an IV.[39] This little estate, which was the old domain of Beauregard, was a modest farm-house or country-house at Héricourt-Saint-Samson, in the Department of Seine-et-Oise, not far to the northward of Beauvais, and about fifty miles from Paris. It is probable that as a proprietor of a landed property he passed the summer season, or a part of it, on this estate.

This request was, we may believe, made from no unworthy or mercenary motive, but because he thought that such an indemnity was his due. Some years after (in 1809) the chair of zoölogy, newly formed by the Faculté des Sciences in Paris, was offered to him. Desirable as the salary would have been in his straitened circumstances, he modestly refused the offer, because he felt unable at that time of life (he was, however, but sixty-five years of age) to make the studies required worthily to occupy the position.

One of Lamarck's projects, which he was never able to carry out, for it was even then quite beyond the powers of any man single-handed to undertake, was his _Système de la Nature_. We will let him describe it in his own words, especially since the account is somewhat autobiographical. It is the second memoir he addressed to the Committee of Public Instruction of the National Convention, dated 4 vendémiaire, l'an III. (1795):

"In my first memoir I have given you an account of the works which I have published and of those which I have undertaken to contribute to the progress of natural history; also of the travels and researches which I have made.

"But for a long time I have had in view a very important work--perhaps better adapted for education in France than those I have already composed or undertaken--a work, in short, which the National Convention should without doubt order, and of which no part could be written so advantageously as in Paris, where are to be found abundant means for carrying it to completion.

"This is a _Système de la Nature_, a work analogous to the _Systema naturæ_ of Linnæus, but written in French, and presenting the picture complete, concise, and methodical, of all the natural productions observed up to this day. This important work (of Linnæus), which the young Frenchmen who intend to devote themselves to the study of natural history always require, is the object of speculations by foreign authors, and has already passed through thirteen different editions. Moreover, their works, which, to our shame, we have to use, because we have none written expressly for us, are filled (especially the last edition edited by Gmelin) with gross mistakes, omissions of double and triple occurrence, and errors in synonymy, and present many generic characters which are inexact or imperceptible and many series badly divided, or genera too numerous in species, and difficulties insurmountable to students.

"If the Committee of Public Instruction had the time to devote any attention to the importance of my project, to the utility of publishing such a work, and perhaps to the duty prescribed by the national honor, I would say to it that, after having for a long time reflected and meditated and determined upon the most feasible plan, finally after having seen amassed and prepared the most essential materials, I offer to put this beautiful project into execution. I have not lost sight of the difficulties of this great enterprise. I am, I believe, as well aware of them, and better, than any one else; but I feel that I can overcome them without descending to a simple and dishonorable compilation of what foreigners have written on the subject. I have some strength left to sacrifice for the common advantage; I have had some experience and practice in writing works of this kind; my herbarium is one of the richest in existence; my numerous collection of shells is almost the only one in France the specimens of which are determined and named according to the method adopted by modern naturalists--finally, I am in a position to profit by all the aid which is to be found in the National Museum of Natural History. With these means brought together, I can then hope to prepare in a suitable manner this interesting work.

"I had at first thought that the work should be executed by a society of naturalists; but after having given this idea much thought, and having already the example of the new encyclopædia, I am convinced that in such a case the work would be very defective in arrangement, without unity or plan, without any harmony of principles, and that its composition might be interminable.

"Written with the greatest possible conciseness, this work could not be comprised in less than eight volumes in 8vo, namely: One volume for the quadrupeds and birds; one volume for the reptiles and fishes; two volumes for the insects; one volume for the worms (the molluscs, madrepores, lithophytes, and naked worms); two volumes for the plants; one volume for the minerals: eight volumes in all.

"It is impossible to prepare in France a work of this nature without having special aid from the nation, because the expense of printing (on account of the enormous quantity of citations and figures which it would contain) would be such that any arrangement with the printer or the manager of the edition could not remunerate the author for writing such an immense work.

"If the nation should wish to print the work at its own expense, and then give to the author the profits of the sale of this edition, the author would be very much pleased, and would doubtless not expect any further aid. But it would cost the nation a great deal, and I believe that this useful project could be carried through with greater economy.

"Indeed, if the nation will give me twenty thousand francs, in a single payment, I will take the whole responsibility, and I agree, if I live, that before the expiration of seven years the _Système de la Nature_ in French, with the complemental addition, the corrections, and the convenient explanations, shall be at the disposition of all those who love or study natural history."

FOOTNOTES:

[32] Most men of science of the Revolution, like Monge and others, were advanced republicans, and the Chevalier Lamarck, though of noble birth, was perhaps not without sympathy with the ideas which led to the establishment of the republic. It is possible that in his walks and intercourse with Rousseau he may have been inspired with the new notions of liberty and equality first promulgated by that philosopher.

His studies and meditations were probably not interrupted by the events of the Terror. Stevens, in his history of the French Revolution, tells us that Paris was never gayer than in the summer of 1793, and that during the Reign of Terror the restaurants, _cafés_, and theatres were always full. There were never more theatres open at the same period than then, though no single great play or opera was produced. Meanwhile the great painter David at this time built up a school of art and made that city a centre for art students. Indeed the Revolution was "a grand time for enthusiastic young men," while people in general lived their ordinary lives. There is little doubt, then, that the savants, except the few who were occupied by their duties as members of the _Convention Nationale_, worked away quietly at their specialties, each in his own study or laboratory or lecture-room.

[33] Bern. Germ. Étienne, Comte de Lacépède, born in 1756, died in 1825, was elected professor of the zoölogy of "quadrupedes ovipares, reptiles, et poissons," January 12, 1795 (Records of the Museum). He was the author of works on amphibia, reptiles, and mammals, forming continuations of Buffon's _Histoire Naturelle_. He also published _Histoire Naturelle des Poissons_ (1798-1803), _Histoire des Cétacés_ (1804), and _Histoire Naturelle de l'Homme_ (1827), _Les Ages de la Nature et Histoire de l'Espèce Humaine_, tome 2, 1830.

[34] Perrier, _l. c._, p. 14.

[35] _Fragments Biographiques_, p. 214.

[36] _Fragments Biographiques_, p. 213.

[37] A few years ago, when we formed the plan of writing his life, we wrote to friends in Paris for information as to the exact house in which Lamarck lived, and received the answer that it was unknown; another proof of the neglect and forgetfulness that had followed Lamarck so many years after his death, and which was even manifested before he died. Afterwards Professor Giard kindly wrote that by reference to the _procès verbaux_ of the Assembly, it had been found by Professor Hamy that he had lived in the house of Buffon.

The house is situated at the corner of Rue de Buffon and Rue Geoffroy St. Hilaire. The courtyard facing Rue Geoffroy St. Hilaire bears the number 2 Rue de Buffon, and is in the angle between the Galerie de Zoologie and the Bibliothèque. The edifice is a large four-storied one. Lamarck occupied the second _étage_, what we should call the third story; it was first occupied by Buffon. His bedroom, where he died, was on the _premier étage_. It was tenanted by De Quatrefages in his time, and is at present occupied by Professor G. T. Hamy; Professor L. Vaillant living in the first _étage_, or second story, and Dr. J. Deniker, the _bibliothécaire_ and learned anthropologist, in the third. The second _étage_ was, about fifty years ago (1840-50), renovated for the use of Fremy the chemist, so that the exact room occupied by Lamarck as a study cannot be identified.

This ancient house was originally called _La Croix de Fer_, and was built about two centuries before the foundation of the Jardin du Roi. It appears from an inspection of the notes on the titles and copies of the original deeds, preserved in the Archives, and kindly shown me by Professor G. T. Hamy, the Archivist of the Museum, that this house was erected in 1468, the deed being dated _1xbre_, 1468. The house is referred to as _maison ditte La Croix de Fer_ in deeds of 1684, 1755, and 1768. It was sold by Charles Roger to M. le Compte de Buffon, March 23, 1771. One of the old gardens overlooked by it was called _de Jardin de la Croix_. It was originally the first structure erected on the south side of the Jardin du Roi.

[38] In the "avertissement" to his _Système des Animaux sans Vertèbres_ (1801), after stating that he had at his disposition the magnificent collection of invertebrate animals of the museum, he refers to his private collection as follows: "Et une autre assez riche que j'ai formée moi-même par près de trente années de recherches," p. vii. Afterwards he formed another collection of shells named according to his system, and containing a part of the types described in his _Histoire Naturelle des Animaux sans Vertèbres_ and in his minor articles. This collection the government did not acquire, and it is now in the museum at Geneva. The Paris museum, however, possesses a good many of the Lamarckian types, which are on exhibition (Perrier, _l. c._, p. 20).

[39] _Lettre du Ministre des Finances (de Ramel) au Ministre de l'Intérieur_ (13 pr. an V.). See Perrier, _l. c._, p. 20.