194 HUMAN FOSSILS m 



follows : Beaver, 70 to 100 ; Lemur, 119 to 100 ; Baboon. 144 

 to 100. In an adult male Gorilla the cerebral length is as 170 

 to the basicrauial axis taken as 100, in the Negro (Fig. 30) as 

 236 to 100. In the Constantinople skull (Fig. 30) it is as 266 

 to 100. The difference between the highest Ape's skull and the 

 lowest Man's is therefore very strikingly brought out by these 

 measurements. 



la the diagram of the Baboon's skull the dotted lines d } d? t 

 &e., give the angles of the Lemur's and Beaver's skull, as laid 

 down upon the basicranial axis of the Baboon. The line a b has 

 the same length in each diagram. 



leave the skull. Again, a line drawn through the 

 axis of the face, between the bones called ethmoid 

 and vomer the " basifacial axis " (/. e.) forms an 

 exceedingly obtuse angle, where, when produced, 

 it cuts the " basicranial axis." 



If the angle made by the line I c with a 6, be 

 called the " occipital angle," and the angle made 

 by the line a d with a b be termed the " olfactory 

 angle" and that made by i T with a b the 

 " tentorial angle " then all these, in the mammal 

 in question, are nearly right angles, varying 

 between 80 and 110. The angle e f I, or that 

 made by the cranial with the facial axis, and 

 which may be termed the " cranio-facial angle," is 

 extremely obtuse, amounting, in the case of the 

 Beaver, to at least 150. 



But if a series of sections of mammalian skulls, 

 intermediate between a Rodent and a Man (Fig. 

 29), be examined, it will be found that in the 

 higher crania the basi-cranial axis becomes shorter 

 lelatively to the cerebral length; that the " olfac- 



