bears on this subject: he says, It is a remarkable circumstance, that
the difference between the sexes, as regards the cranial cavity,
increases with the development of the race, so that the male European
excels much more the female, than the negro the negress. Welcker
confirms this statement of Huschke from his measurements of negro and
German skulls. But Vogt admits ( Lectures on Man, Eng. translat.
1864, p. 81) that more observations are requisite on this point.
VOICE AND MUSICAL POWERS.
In some species of Quadrumana there is a great difference between the
adult sexes, in the power of their voices and in the development of the
vocal organs; and man appears to have inherited this difference from
his early progenitors. His vocal cords are about one-third longer than
in woman, or than in boys; and emasculation produces the same effect on
him as on the lower animals, for it arrests that prominent growth of
the thyroid, etc., which accompanies the elongation of the cords. (27.
Owen, Anatomy of Vertebrates, vol. iii. p. 603.) With respect to the
cause of this difference between the sexes, I have nothing to add to
the remarks in the last chapter on the probable effects of the
long-continued use of the vocal organs by the male under the excitement
of love, rage and jealousy. According to Sir Duncan Gibb (28. Journal
of the Anthropological Society, April 1869, p. lvii. and lxvi.), the
voice and the form of the larynx differ in the different races of
mankind; but with the Tartars, Chinese, etc., the voice of the male is
said not to differ so much from that of the female, as in most other
races.
The capacity and love for singing or music, though not a sexual
character in man, must not here be passed over. Although the sounds
emitted by animals of all kinds serve many purposes, a strong case can
be made out, that the vocal organs were primarily used and perfected in
relation to the propagation of the species. Insects and some few
spiders are the lowest animals which voluntarily produce any sound; and
this is generally effected by the aid of beautifully constructed
stridulating organs, which are often confined to the males. The sounds
thus produced consist, I believe in all cases, of the same note,
repeated rhythmically (29. Dr. Scudder, Notes on Stridulation, in
Proc. Boston Soc. of Nat. Hist. vol. xi. April 1868.); and this is
sometimes pleasing even to the ears of man. The chief and, in some
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