‘cerebral length.’ The length of the basicranial axis as to this length, or, in other words, the proportional length of the line g h to that of a b taken as 100, in the three skulls, is as follows:—Bes-ver 70 to 100; Lemur 119 to 100; Baboon 144 to 100. In an adult male Gorilla the cerebral length is as 170 to the basicrannial axis taken as 100, in the Negro (fig. 30) as 236 to 100. In the Constantinople skull (fig. 30) as 266 to 100. The cranial difference between the highest Ape’s skull and the lowest Man’s is therefore very strikingly brought out by these measurements. In the digram of the Baboon’s skull the dotted lines d d &c. give the angles

ABSTRACT

It will be obvious, from an inspection of the diagrams, that the basicranial axis is, in the ascending series of Mammalia, a relatively fixed line, on which the bones of the sides and roof of the cranial cavity, and of the face, may be to revolve downwards and forwards or backwards, accord-ing to their position. The are described by any one bone or plane, however, is not by any means always in proportion to the are described by another.