much the same thing,' as may be seen p. 200 of this volume. But the authorship is immaterial; whether the passage was by Dr. Darwin or M. Deleuze, it was, in all probability, known to Lamarck before his change

of front.

The note on Trapa Natans again' suggests itself as the source from which the passage in the Philosophie Zoologique about the Ranunculus aquatilis is taken,3 while one of the most important passages in the work, a summary, in fact, of the principal means of modification, seems to be taken, the first half of it from Buffon, and the second from Dr. Darwin. I have called attention to it on pp. 264, 265.

We may then suppose that Lamarck failed to underStand Buffon, and conceived that he ought either to have gone much farther, or not so far; not being yet prepared to go the whole length himself, he opposed mutability till Dr. Darwin's additions to Buffon's ostensible theory reached him, whereon he at once adopted them, and having received nothing but a few notes and hints, felt himself at liberty to work the theory out independently and claim it. In so original a work as the Philosophie Zoologique must always be considered, this may be legitimate, but I find in it, as Isidore Geoffroy seems also to have found, a little more claim to complete independence than is acceptable to one who is fresh from Buffon and Dr. Darwin.

1

Zoonomia, vol. i, p. 507.

Zoonom, Vol. i, p. 231, ed. M. Martins, 1873.

2 Les Amours des Plantes, p. 360.

T

HE FIRST PART OF THE PHILOSOPHIE Zoologique is the one which deals with the doctrine of evolution or descent with modification. It is to this, therefore, that our attention will be confined. Yet only a comparatively small part of the three hundred and fifty pages which constitute Lamarck's first part are devoted to setting forth the reasons which led him to arrive at his conclusions-the greater part of the volume being occupied with the classification of animals, which we may again omit, as foreign to our purpose.

I shall condense whenever I can, but I do not think the reader will find that I have left out much that bears upon the argument. I shall also use inverted commas while translating with such freedom as to omit several lines together, where I can do so without suppressing anything essential to the elucidation of Lamarck's meaning. I shall, however, throughout refer the reader to the page of the original work from which I am translating.

"The common origin of bodily and mental phenomena," says Lamarck in his preliminary chapter, "has been obscured, because we have studied them chiefly in man, who, as the most highly developed of living beings, presents the problem in its most difficult and complicated aspect. If we had begun our study with that of the lowest organisms, and had proceeded from these to the more complex ones, we should have seen the progression which is observable in organization, and the successive acquisition of various special organs, with new faculties for every additional organ. We should thus have seen that sense of needs-originally hardly perceptible, but gradually increasing in intensity and variety-has led to the attempt to gratify them; that the actions thus induced, having become habitual and

energetic, have occasioned the development of organs adapted for their performance; that the force which excites organic movements can in the case of the lowest animals exist outside them and yet animate them; that this force was subsequently introduced into the animals themselves, and fixed within them; and, lastly, that it gave rise to sensibility and, in the end, to intelligence." The reader had better be on his guard here, and whenever Lamarck is speculating about the lowest forms of action and sensation. I have thought it well, however, to give enough of these speculations, as occasion arises, to show their tendency.

66

Sensation is not the proximate cause of organic movements. It may be so with the higher animals, but it cannot be shown to be so with plants, nor even with all known animals. At the outset of life there was none of that sensation which could only arise where organic beings had already attained a considerable development. Nature has done all by slow gradations, both organs and faculties being the outcome of a progressive development.2

"The mere composition of an animal is but a small part of what deserves study in connection with the animal itself. The effects of its surroundings in causing new wants, the effects of its wants in giving rise to actions, those of its actions in developing habits and tendencies, the effects of use and disuse as affecting any organ, the means which nature takes to preserve and make perfect what has been already acquired-these are all matters of the highest importance.3

"In their bearing upon these questions the invertebrate animals are more important and interesting than the vertebrate, for they are more in number, and being 1 Phil. Zool., vol. i, edited by M. Martins, 1873, pp. 25, 26. 2 Ibid., pp. 26, 27.

3

Ibid., p. 28.

more in number are more varied; their variations are more marked, and the steps by which they have advanced in complexity are more easily observed.1

"I propose, therefore, to divide this work into three parts, of which the first shall deal with the conventions necessary for the treatment of the subject, the importance of analogical structures, and the meaning which should be attached to the word species. I will point out on the one hand the evidence of a graduated descending scale, as existing between the highest and the lowest organisms; and, on the other, the effect of surroundings and habits on the organs of living beings, as the cause of their development or arrest of development. Lastly, I will treat of the natural order of animals, and show what should be their fittest classification and arrangement." 2

It seems unnecessary to give Lamarck's intentions with regard to his second and third parts, as they do not here concern us; they deal with the origin of life and mind.

The first chapter of the work opens with the importance of bearing in mind the difference between the conventional and the natural, that is to say, between words and things. Here, as indeed largely throughout this part of his work, he follows Buffon, by whom he is evidently influenced.

"The conventional deals with systems of arrangement, classification, orders, families, genera, and the nomenclature, whether of different sections or of individual objects.

"An arrangement should be called systematic, or arbitrary, when it does not conform to the genealogical order taken by nature in the development of the things arranged, and when, by consequence it is not founded Phil. Zool., vol. i, pp. 28-31. 2 Ibid., pp. 34, 35.

upon well-considered analogies. There is such a thing as a natural order in every department of nature; it is the order in which its several component items have been successively developed.1

"Some lines certainly seem to have been drawn by Nature herself. It was hard to believe that mammals, for example, and birds, were not well-defined classes. Nevertheless the sharpness of definition was an illusion, and due only to our limited knowledge. The ornithorhynchus and the echidna bridge the gulf.2

"Simplicity is the main end of any classification. If all the races, or as they are called, species, of any kingdom were perfectly known, and if the true analogies between each species, and between the groups which species form, were also known, so that their approximations to each other and the position of the several groups were in conformity with the natural analogies between them-then classes, orders, sections, and genera would be families, larger or smaller; for each division would be a greater or smaller section of a natural order or sequence. But in this case it would be very difficult to assign the limits of each division; they would be continually subjected to arbitrary alteration, and agreement would only exist where plain and palpable gaps were manifest in our series. Happily, however, for classifiers there are, and will always probably remain, a number of unknown forms." 4

That the foregoing is still felt to be true by those who accept evolution, may be seen from the following passage, taken from Mr. Darwin's Origin of Species:

"As all the organic beings which have ever lived can be arranged within a few great classes; and as all within each class have, according to our theory, been 'Phil. Zool., vol. i, P: 42. 2 Ibid., p. 46. 3 Ibid., p. 50.

4

• Ibid., pp. 50, 51.

3