| OCR Text |
Show 22 THE DESCENT OF MAN. PART I. which from inhabiting oceanic islands have not been exposed to the attacks of beasts of prey, and have consequently lost the power of using their wings for flight. The celebrated sculptor, Mr. Woolner, informs me of one little peculiarity in the external ear, which he has often observed both in men and women, and of which he perceived the full signification. His attention was first called to the subject whilst at work on his figure of Puck, to which he had given pointed cars. He was thus led to examine the ears of various monkeys, and subsequently more carefully those of man. The peculiarity consists in a little blunt point, projecting from the inwardly folded margin, or helix. 1\Ir. vVoolner made an exact model of one such case, and has sent me the accompanying drawing. (Fig. 2.) These points not only project inw·ards, but often a little a outwards, so that they are visible when the head is viewed from directly in front or behind. They are variable in size and somewhat in position, standing either a little higher or lower; and they sometimes occur on one ear and not on the other. Now the mean- Fig. 2. Ruman Ear, modelled ing of these projections is not, and drawn by Mr. Woolner. a. The projecting point. I think, doubtful; but it may be thought that they offer too trifling a character to be worth notice. This thought, howeYer, is as false as it is natural. Every character, however slight, must be the result of some definite cause; and if it occurs in many individuals deserves consideration. The helix obviously consists of the extreme margin of the ear folded inwards; and this folding appears to be in some manner connected with the CHAP. I. RUDIMENTS. 23 whole external ear being permanently pressed backwards. In many monkeys, which do not stand high in the order, as baboons and some species of macacus,25 the upper portion of the ear is slightly pointed, and the margin is not at all folded inwards; but if the margin were to be thus folded, a slight point would necessarily project inwards and probably a little outwards. This could actually be observed in a specimen of the Ateles beelzebuth in the Zoological Gardens; and we may safely conclude that it is a similar structure-a vestige of formerly pointed ears-which occasionally reappears in man. The nictitating membrane, or third eyelid, with its .accessory muscles and other structures, is especially well developed in birds, and is of much functional importance to them, as it can be rapidly drawn across the whole eye-ball. It is found in some reptiles and amphibians, and in certain fishes, as in sharks. It is fairly well developed in the two lower divisions of the mammalian series, namely, in the monotremata and marsupials, and in some few of the higher mammals, as in the walrus. But in man, the quadrumana, and most other mammals, it exists, as is admitted by all anatomists, as a mere rudiment, called the semilunar fold.26 The sense of smell is of the highest importance to the greater number of mammals-to some, as the ruminants, in warning them of danger; to others, as the 2 " Sec also some remarks, and the drawing:> of the cars of the Lemuroidea, in Messrs. Murie and Mivart's excellent paper in 'Transact. Zoolog. Soc.' vol. vii. 1869, pp. 6 and 90. 26 Muller's 'Elements of Physiology,' Eng. translat., 1842, vol. ii. p. 1117. Owen,' Anatomy of Vertebrates,' vol. iii. p. 260; ibid. on the Walrus,' Proc. Zoolog. Soc.' November 8th, 1854. See also R. Knox, 4 Great Artists and Anatomists,' p. lOG. This rudiment apparently is .somewhat larger in Negroes and Australians than in Emopeans, see Carl Vogt, 'Lectures on Man,' Eng. translat. p. 129. |
