the want relative to the other sex. But in pro- 

 portion as these organs increase and become ac- 

 tive, a new faculty, a new propensity is awakened 

 in the interior man ; and it is the sense of this 

 propensity which we call want. Does the object 

 which is in relation with this propensity offer it- 

 self to the eyes of the young man, or the young 

 girl? their blood is roused; while, on the contrary, 

 the same objects being no longer in relation with 

 the now worn-out organisation of the old man, 

 fail to excite him. Do the limbs develop them- 

 selves in the young animal or in the man? the 

 necessity of walking, jumping, running, and of 

 exercising themselves in all sorts of tricks and 

 sports, is likewise felt. It is not because the 

 bird has need of a nest, the beaver of a house, 

 that they acquire the talent of building; but they 

 have this talent because they are destined to 

 build; nature has, in a manner, impregnated 

 their organisation with this talent; and when this 

 organisation becomes active, they are internally 

 prompted to build. Hence it is, that the weaver- 

 bird forms her tissue even when encaged; and 

 hence the beaver builds, however well lodged he 

 may be already. Nothing shows better that in 

 this they follow the impulse of an internal faculty, 

 without being determined by any external neces- 

 sity. There are, likewise, men for whom travel- 

 ling, music, &c, are almost matters of necessity; 

 because in these individuals, the organs which 

 correspond to these propensities possess a pre- 

 dominant activity. It is, again, by the same 

 principle, that we must explain, why men who 

 have several organs eminently developed, experi- 

 ence a greater number of wants than those whose 

 organs are less energetic. The idiot has few de- 

 sires, consequently iew wants; and he has few 

 desires, because few of his organs arrive at com- 

 plete development, or any considerable degree 

 of activity. As we advance in age, our internal 

 wants diminish, because the activity of the or- 

 gans is impaired. 



If, then, the internal wants are the result of 

 the action of the cerebral organs, and if external 

 things cannot become the object of our Avants, 

 except by means of these same organs, the asser- 

 tion of M, de Lamark falls of itself. This au- 

 thor thinks, that the internal organs, as well as 

 the external, are produced by necessity and by ex- 

 ercise. But a necessity can no more exist with- 

 out a faculty, than the exercise of the faculty can 

 exist without an organ. For the rest, as I do 

 not believe that this strange opinion will find 

 many partisans, I am going to present the lead- 

 ing idea of it, and to reply to it in a few words: 

 Naturalists, says M. de Lamark, having remarked 

 that the forms of the parts of animals, compared 

 with the uses of these parts, are alwa} r s in perfect 

 relation, have thought that the forms and the state 

 of the parts may have led to their use. Now this is 

 an error; for, it is easy to show by observation, 

 that it is, on the contrary, the necessities and the 

 uses of the parts, which have developed these 

 parts, which have given birth to them where they 

 did not exist; and which, consequent^, have 

 given place to the state where we observe them in 

 each animal. 



Thus, M. de Lamark supposes, that the sense 

 of necessity exists before the internal organs, and 

 that the exercise of the external organs precedes 



the existence of these organs: "The mole," says 

 he, "preserves her little eyes, only because she 

 exercises them but for little; serpents,having adopt- 

 ed the habit of crawling on the ground, and of 

 hiding themselves under the grass, their body, by 

 a succession of still repeated efforts to elongate 

 themselves in order to pass into narrow passages, 

 acquires a considerable length, out of all propor- 

 tion to their size." Men, moved by the necessity of 

 bearing rule, and of directing their vision both 

 far and wide, have found themselves obliged to 

 stand upright; and this custom having been 

 adopted, from generation to generation, their feet 

 have acquired a conformation fitted to maintain 

 them in a perpendicular position. 



But what will M. de Lamark answer to the 

 following questions? Why does not the mole 

 make use of its eyes, and why has the serpent 

 the foolish notion of crawling on the ground, and 

 passing through narrow holes, as the wire passes 

 under the drawing iron? Whence comes in man 

 the propensity to look far and wide? And, in the 

 beginning, when there existed neither interior nor 

 exterior organ, Avhat prevented the mole and the 

 serpent from adopting different habits of life, 

 and thus acquiring the eyes of the eagle, and the 

 legs of the giraffe? How can we believe that 

 Supreme Wisdom has not placed each animal in 

 harmony with his external world, and conse- 

 quently the internal faculties in accordance with 

 the external organs? Without this harmony, 

 animals would be found in a violent state of 

 perpetual contradiction, or would have perished 

 after a few moments of existence. The tiger 

 would have been destined to feed on flesh ; but 

 have received neither the inclination nor the 

 faculty to destroy other animals. The bird would 

 have been intended to migrate from one climate 

 to another; but nothing in his_ internal 

 organisation would have warned him of it, 

 and, perhaps, wings would have been wanting 

 with which to fly. The bull would have been 

 destined to pasture ; but he would neither possess 

 scent to choose salutary plants, nor the teeth pro- 

 per for their due mastication. 



And, into what difficulties should we not fall 

 in fixing the limits, where the production and 

 augmentation of external organs should finally be 

 arrested. Man, to whom his two hands are often 

 insufficient,— would he always content himself to 

 have only two? Would not eyes make their ap- 

 pearance on his back? How much would the 

 legs of the heron and the stork, and the neck of 

 the swan bo still more lengthened ? On the con- 

 trary, from the time of Aristotle, these _ £arts 

 have been as long as they now are: how is this 

 to'be explained? Is it, as M. de Lamark says, 

 because birds have always remained in the same 

 circumstances? But, in stating this, he recognises 

 the principle, that nature originally prescribed 

 to them to keep themselves in these circumstances. 

 What cause could have prevented the marsh birds 

 from gradually going deeper in the water, and 

 from lengthening their feet and necks more and 

 more by the continuance of their efforts? _ Why 

 should cats, rats, and sheep, who use their tails 

 so little, not have lost them wholly ere this? To 

 what extent might not the power be increased 

 possessed by animals, of augmenting the num- 

 ber of their limbs, or of being transformed from 



