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Show 22 THE PRESENT CONDITION But let me ask you to look along these diagrams, I-Iere is the skeleton of the llorse, and here the s1 ( e 1e t on o f the Dob()" ' You will notice that we have in the I-Iorse a skull, a backbone and ribs, shoulder-blades and haunch-bones. In the fore-limb, one upper ar.m -bone , two fore arm-bones, wrist-bon. es (wrongly called knee), and middle hand-bones, ending in the three bones of a finger, the last of which is sheathed in the horny hoof of the fore-foot: in the }1ind-limb, one thigh-bone, two leg-bones, ankle-bon'es, and middle foot-bones, ending in the three bones of a toe the last of which is encased in the hoof of the ) hind-foot. Now turn to the Dog's skeleton. vv'" c find identically the same bones, but more of them, there being more toes in each foot, and hence rnore toe-bones. Well, that is a very curious thing ! The fact is that the Dog and the Horse-when one gets a look at them without the outward impediments of the skinare found to be made in very much the same sort of fashion. And if I were to make a transverse section of the Dog, I should find the same organs that I have already shown you as forming parts of the I-Iorse. Well, here is another skelet0n-that of a kind of Lemur -you see he has just the same bones; and if I were to make a transverse section of it, it would be just the same again. In your mind's eye turn him round, so as to put his backbone in a position inclined obliquely upwards and forwards, just as in the next three diagrams, which represent the skeletons of an Orang, a Chimpanzee, a Gorilla, and you find you have no trouble in identifying the bones throughout; and lastly turn to OF ORGA~IC NATURE. 23 the end of the series, the diagram representing a man's skeleton, and still you find no great structural feature essentially altered. There are the same bones in the same relations. From the I-Iorse we pass on and on, with gradual steps, until we arrive at last at the highest known forms. On the other hand, take the other line of diarrrams and pass from the Horse down wards in the scale b ' to this fish; and still, though the modifications are vastly c>'reater the essential framework of the organization b ) remains unchanged. Here, for instance, is a Porpoise; here is its strong backbone, with the cavity running through it, which contains the spinal cord; here are the ribs, here the shoulder-blade; here is the little short upper-arm bone, here are the two forearm bones. the wrist-bone, and the finger-bones. Strange, is it not, that the Porpoise should have in this queer-looking affair-its flapper (as it is called), the sa1ne fundamental elements as the fore-leg of the Horse or the Dog, or the Ape or Man; and here you will notice a very curious thing,-the hinder limbs are absent. Now, let us make another jump. Let us go to the Codfish: here you see is the forearm, in this large pectoral fin-carrying your 1nind's eye onward from the flapper of the Porpoise. And here you have the hinder limbs restored in the shape of these ventral fins. If I were to make a transverse section of this, I should find just the same organs that we have before noticed. So that, you see, there comes out this strange conclusion as the result of our investigations, that the I-Iorse, when examined and compared with other animals, is found by no means to stand alone in nature; but that there are an enormous nun1ber of other |