sometimes possess the arrangement of tendons of thumb and fingers
characteristic of the macaque; but whether such a case should be regarded
as a macaque passing upwards into a man, or a man passing downwards into a
macaque, or as a congenital freak of nature, I cannot undertake to say."
It is satisfactory to hear so capable an anatomist, and so embittered an
opponent of evolutionism, admitting even the possibility of either of his
first propositions. Prof. Macalister has also described ('Proceedings
Royal Irish Academy,' vol. x. 1864, p. 138) variations in the flexor
pollicis longus, remarkable from their relations to the same muscle in the
Quadrumana.)

That this unknown factor is reversion to a former state of existence may be
admitted as in the highest degree probable. (54. Since the first edition
of this book appeared, Mr. Wood has published another memoir in the
Philosophical Transactions, 1870, p. 83, on the varieties of the muscles of
the human neck, shoulder, and chest. He here shews how extremely variable
these muscles are, and how often and how closely the variations resemble
the normal muscles of the lower animals. He sums up by remarking, "It will
be enough for my purpose if I have succeeded in shewing the more important
forms which, when occurring as varieties in the human subject, tend to
exhibit in a sufficiently marked manner what may be considered as proofs
and examples of the Darwinian principle of reversion, or law of
inheritance, in this department of anatomical science.") It is quite
incredible that a man should through mere accident abnormally resemble
certain apes in no less than seven of his muscles, if there had been no
genetic connection between them. On the other hand, if man is descended
from some ape-like creature, no valid reason can be assigned why certain
muscles should not suddenly reappear after an interval of many thousand
generations, in the same manner as with horses, asses, and mules, dark-
coloured stripes suddenly reappear on the legs, and shoulders, after an