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Show 1897.] OF HAIR UPON THE HUMAN EAR. 307 anything as to the shape, position, and movements of the ancestral ear? As to shape, it seems unlikely that the ear was obtusely pointed as in Loris and Cynocephalus, for had not the point been originally at least as sharp as it is in Macacus it would hardly have persisted until now. As to position and mobility: was the ear pressed as closely to the head as in most living Apes, and had it as little mobility as theirs ? Darwin ascertained l that neither the Orang nor the Chimpanzee ever erects or moves its ears. I have seen Macacus maurus move its ear slightly, and some men retain this power, although it is questionable whether this movement is due to the extrinsic muscles of the organ, as Darwin appears to have believed2, or to the contraction of the scalp. It is certain that beyond the power possessed by many persons of moving their ears simultaneously with their eyebrows and the skin of the nape, some few can move the whole ear quite independently of the scalp ; and I have observed a case in which the upper half of the ear could be vibrated at will, either rapidly or slowly, whilst the lobe and lower half of the same organ, the eyebrows, and scalp remained motionless. Whether these movements are due to the muscles of the ear or no, such muscles exist in M a n , and their existence argues past use in our ancestral form. As a matter of fact the external ear in both M a n and the Quadrumana is an atrophied organ in several respects, mobility for one. But evidence of mobility is foreign to the present enquiry except as affording concurrent testimony as to the conditions of the ancestral ear, which almost certainly moved freely. A freely moving ear must needs project, and a projecting ear is exposed and seems to require (and usually possesses) a special hairy covering of its own. To-day the normal human ear is almost hairless, frequently indeed quite nude. It is practically sessile. Whether at one time it projected laterally seems a fair subject for investigation, and to this question the existence of hairs upon its back affords a clue. Where the ear is pressed closely to the head as in most of the Quadrumana, its back is almost naked : it was quite bare in the Gibbon which I examined. A n ear thus placed is obviously protected from weather either by the fur in which it is embedded, as in the Gibbon, or by tbe long tresses wdiich fall over it from the sides of the head in the Orang and Chimpanzee 3. Even the thick short bristly hair of the Gorilla affords an efficient protection, and it is not easy to get sight of the back of its ears, even wdien the ear is handled. A special hairy covering for an ear so placed is needless, a tuft in the orifice to exclude rain being all that is needed and usually all that exists. Except a very few weak hairs in Gorilla, the Anthropoids have lost the hair upon the back of the ear so far as m y observations extend, which is not far, for Anthropoid Apes 1 ' Descent of Man,' 1871, i. p. 21. 2 Ibid. p. 20. 1 Troylodytes calvus, as its name implies is bald. |