The Descent of Man

sented this muscle; and in the remaining eighteen
no trace of it. In only two out of thirty female
subjects was this muscle developed on
both sides, but in three others the rudimentary
ligament was present. This muscle, therefore,
appears to be much more common in the male
than in the female sex; and on the belief in the
descent of man from some lower form, the fact
is intelligible; for it has been detected in several
of the lower animals, and in all of these it serves
exclusively to aid the male in the act of reproduction.
Mr. J. Wood, in his valuable series of papers
(48. These papers deserve careful study by any
one who desires to learn how frequently our
muscles vary, and in varying come to resemble
those of the Quadrumana. The following references
relate to the few points touched on in my
text: 'Proc. Royal Soc.' vol. xiv. 1865, pp. 379-
384; vol. xv. 1866, pp. 241, 242; vol. xv. 1867, p.
544; vol. xvi. 1868, p. 524. I may here add that