16 Dusois—On Pithecanthropus erectus : 
human model than the simian. Sir William Turner,* on the contrary, inclines 
to ascribing the tooth to an Orang-utan, and doubts, on account of its large size, 
that it could have belonged toa man. In Manouvrier’s estimation the tooth is, 
through its dimensions, simian; through the crown surface, however, more 
human.f 
In close proximity to the place where the skull and the tooth already described 
were found, and in exactly the same level again, a second molar of the left side 
was dug out a year later, but in the same year as the femur. The crown of 
this is in its transverse dimensions a little smaller than that of the third molar; in 
its sagittal dimensions, however, it is somewhat larger. The roots are a little 
shorter, but as strongly divergent, and in the same way directed obliquely back- 
ward. They are, in both molars, modelled after exactly the same type, so that for 
these reasons alone the connexion of these two would be highly probable; but also 
the crenation of the crown is the same as that of the third molar; the dimensions, 
as I said, are not very different, and it shows a similar, relatively strong retro- 
gression of the cusps, which are of the same type. The crown of the second 
molar is far more worn off, and shows at its circumference in front and behind a 
grinding facet against the neighbouring teeth. The circumstances in which they 
were found, together with the result of their comparison, prove, in my opinion, that 
these two teeth are certainly from the same individual. The objection that they 
cannot belong to the same individual on account of the different degree in which 
their crowns are worn off, was easily set aside by comparing them with teeth in 
the skulls of a Gibbon and an Orang-utan, which I demonstrated at the Leiden 
Congress, as also several human skulls. In these the third molar had only been a 
short time in function, just as the wisdom-tooth of the Pithecanthropus, whilst 
the other two molars already showed a strong wearing off. 
Thus the objection that the third molar could not belong to the skull-cap, 
because it is certainly from an old individual, is at the same time set aside. 
The crown of the wisdom-tooth being larger than that of the second molar is 
often to be seen in Man. Some pregnant cases I have measured in the rich 
eraniological collection of the Anatomical Museum in Leiden. 
This second molar tooth shows a similar retrogression of the crown as the 
third. Nevertheless, like the third molar, it is of the simian type. In Man, 
of the four cusps on the crown of the upper molars, the smallest is the lingual 
posterior cusp. On the contrary, as in the Anthropoids, one of the cusps becomes 
smaller ; it is always the buccal posterior cusp.t Now, of the crown of the second 
molar tooth from Trinil, the duceal posterior cusp is in retrogression exactly, 
but in a slighter degree, as in the third molar. The examination of this tooth, 
* “7, ep. 443. dene Demlitie 
t Very rarely the reverse is the case, and only with the third upper molar. 
