HO MAX AND THE LOWER ANIMALS. n 



length in each case, thereby displaying the varying pro- 

 portions of the facial bones. The line b indicates the 

 plane of the tentorium, which separates the cerebrum 

 from the cerebellum ; d, the axis of the occipital outlet of 

 the skull. The extent of cerebral cavity behind c, which 

 is a perpendicular erected on b at the point where the ten- 

 torium is attached posteriorly, indicates the degree to 

 which the cerebrum overlaps the cerebellum — the space 

 occupied by which is roughly indicated by the dark shad- 

 ing. In comparing these diagrams, it must be recollected, 

 that figures on so small a scale as these simply exemplify 

 the statements in the text, the proof of which is to be 

 found in the objects themselves. 



same parts which characterises the Baboon, and 

 yet more remarkably distinguishes the Lemur. 



Similarly, the occipital foramen of Mycetes 

 (Fig. 17), and still more of the Lemurs, is situated 

 completely in the posterior face of the skull, or as 

 much further back than that of the Gorilla, as 

 that of the Gorilla is further back than that of 

 Man; while, as if to render patent the futility of 

 the attempt to base any broad classificatory distinc- 

 tion on such a character, the same group of Platy- 

 rhine, or American monkeys, to which the Mycetes 

 belongs, contains the Clirysotlirix, whose occipital 

 foramen is situated far more forward than in any 

 other ape, and nearly approaches the position it 

 holds in Man. 



Again, the Orang's skull is as devoid of exces- 

 sively developed supraciliary prominences as a 

 Man's, though some varieties exhibit great crests 

 elsewhere (See p. 25); aud in some of the Cebine 

 apes and in the Chrysothrix, the cranium is as 

 smooth and rounded as that of Man himself. 



