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The Descent of Man by Charles Darwin
page 38 of 1105 (03%)
hairy. Three or four cases have been recorded of persons born with their
whole bodies and faces thickly covered with fine long hairs; and this
strange condition is strongly inherited, and is correlated with an abnormal
condition of the teeth. (41. See my 'Variation of Animals and Plants
under Domestication,' vol. ii. p. 327. Prof. Alex. Brandt has recently
sent me an additional case of a father and son, born in Russia, with these
peculiarities. I have received drawings of both from Paris.) Prof. Alex.
Brandt informs me that he has compared the hair from the face of a man thus
characterised, aged thirty-five, with the lanugo of a foetus, and finds it
quite similar in texture; therefore, as he remarks, the case may be
attributed to an arrest of development in the hair, together with its
continued growth. Many delicate children, as I have been assured by a
surgeon to a hospital for children, have their backs covered by rather long
silky hairs; and such cases probably come under the same head.

It appears as if the posterior molar or wisdom-teeth were tending to become
rudimentary in the more civilised races of man. These teeth are rather
smaller than the other molars, as is likewise the case with the
corresponding teeth in the chimpanzee and orang; and they have only two
separate fangs. They do not cut through the gums till about the
seventeenth year, and I have been assured that they are much more liable to
decay, and are earlier lost than the other teeth; but this is denied by
some eminent dentists. They are also much more liable to vary, both in
structure and in the period of their development, than the other teeth.
(42. Dr. Webb, 'Teeth in Man and the Anthropoid Apes,' as quoted by Dr. C.
Carter Blake in Anthropological Review, July 1867, p. 299.) In the
Melanian races, on the other hand, the wisdom-teeth are usually furnished
with three separate fangs, and are generally sound; they also differ from
the other molars in size, less than in the Caucasian races. (43. Owen,
'Anatomy of Vertebrates,' vol. iii. pp. 320, 321, and 325.) Prof.
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