The Prehistoric Find at Piltdown. 215 
cranium which showed a correlation in shape, in structure, and in its muscle 
markings, and such correlation is not shown by the human skull represented 
by the cranial fragments. 
The Characters of the Teeth of Man and Apes.—The anterior teeth of the 
mandible of the apes show characters which distinguish them clearly from 
human teeth. The incisors are large and stout, the canine teeth are thick 
and so long as to project beyond the level of the crowns of the teeth. The 
premolar teeth show less difference, and the molar teeth generally resemble 
those of man, but are longer, narrower and have a thicker enamel. 
The human characters, which were stated to be shown by the Piltdown 
molars, were the flattening of the crown, by wear, and the thinness of the 
enamel. They were stated to be “distinctly human, though of the most 
primitive type, and reminiscent of the ape’s in their narrowness.” I did not 
at first feel myself qualified to speak with certainty upon the differences 
which can be relied upon to distinguish human and anthropoid teeth, and 
I have not been able to examine a sufficiently large range of specimens to 
be able to speak from.my own observations. I can, however, put before you 
the very striking facts which have recently been published by Mr Miller 
and by Prof. Ramstrom. 
There is a wide range of variation in the teeth of the chimpanzee, and in 
spite of the projecting canines, the molar teeth of adult specimens often show 
a great amount of flattening from grinding down of the surface. 
Mr Miller, dealing with certain specific characters in which the Piltdown 
Specimens were stated to be human, has shown that in the ratio of crown 
height to maximum crown width (degree of “hypsodonty” in Hoanthropus 
represented by the figure 62°8), the teeth fall within the range for the 
chimpanzee, though there is an overlap, and this figure is distinctive of 
neither genus. 
The tubercles are not larger than can be found in the chimpanzee, and 
the size of the pulp cavity is indistinguishable from that in man. In their 
obvious characters the teeth can be matched with those of a chimpanzee. 
Prof. Ramstrom has devised some other tests for relationship, the most 
striking of which is the ratio between the proximo-distal length and 
transverse width. After examining a large series of teeth, he has been 
able to bring out that in human teeth the proximo-distal length is not 
usually greatly different from the width, the difference being not usually 
more than one millimetre, and the ratio of the two measurements does 
not fall below 90. In the chimpanzee, on the other hand, the difference 
between the two measurements is more considerable, 1, 2, or even 3 mm., 
and the ratio runs between 74:6 and 90, In the Piltdown teeth, the 
