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The Descent of Man by Charles Darwin
page 34 of 1105 (03%)
correspondence in position with that of the tip of a pointed ear. In one
case, of which a photograph has been sent me, the projection is so large,
that supposing, in accordance with Prof. Meyer's view, the ear to be made
perfect by the equal development of the cartilage throughout the whole
extent of the margin, it would have covered fully one-third of the whole
ear. Two cases have been communicated to me, one in North America, and the
other in England, in which the upper margin is not at all folded inwards,
but is pointed, so that it closely resembles the pointed ear of an ordinary
quadruped in outline. In one of these cases, which was that of a young
child, the father compared the ear with the drawing which I have given (34.
'The Expression of the Emotions,' p. 136.) of the ear of a monkey, the
Cynopithecus niger, and says that their outlines are closely similar. If,
in these two cases, the margin had been folded inwards in the normal
manner, an inward projection must have been formed. I may add that in two
other cases the outline still remains somewhat pointed, although the margin
of the upper part of the ear is normally folded inwards--in one of them,
however, very narrowly. [Fig.3. Foetus of an Orang(?). Exact copy of a
photograph, shewing the form of the ear at this early age.] The following
woodcut (No. 3) is an accurate copy of a photograph of the foetus of an
orang (kindly sent me by Dr. Nitsche), in which it may be seen how
different the pointed outline of the ear is at this period from its adult
condition, when it bears a close general resemblance to that of man. It is
evident that the folding over of the tip of such an ear, unless it changed
greatly during its further development, would give rise to a point
projecting inwards. On the whole, it still seems to me probable that the
points in question are in some cases, both in man and apes, vestiges of a
former condition.

The nictitating membrane, or third eyelid, with its accessory muscles and
other structures, is especially well developed in birds, and is of much
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