sometimes more strongly developed in the less aged animal. Professor
Temminck states that the series of skulls in the Leyden Museum shows
the same result."

Mr. Wallace observed two male adult Orangs (Mias Kassu of the Dyaks),
however, so very different from any of these that he concludes them to
be specially distinct; they were respectively 3 feet 8½ inches and
3 feet 9½ inches high, and possessed no sign of the cheek excrescences,
but otherwise resembled the larger kinds. The skull has no crest, but
two bony ridges, 1¾ to 2 inches apart, as in the _Simia morio_ of
Professor Owen. The teeth, however, are immense, equalling or
surpassing those of the other species. The females of both these
kinds, according to Mr. Wallace, are devoid of excrescences, and
resemble the smaller males, but are shorter by 1½ to 3 inches, and
their canine teeth are comparatively small, subtruncated and dilated
at the base, as in the so-called _Simia morio_, which is, in all
probability, the skull of a female of the same species as the smaller
males. Both males and females of this smaller species are
distinguishable, according to Mr. Wallace, by the comparatively large
size of the middle incisors of the upper jaw.

So far as I am aware, no one has attempted to dispute the accuracy of
the statements which I have just quoted regarding the habits of the
two Asiatic man-like Apes; and if true, they must be admitted as
evidence that such an ape--

1stly, May readily move along the ground in the erect, or semi-erect,
position, and without direct support from its arms.

2dly, That it may possess an extremely loud voice--so loud as to be