LECTURE VIII. 211 



You perceive from these details, that the skulls of these two 

 species, which some would distinguish as two sub-genera, are 

 much more like each other than the skulls of most human 

 races and even tribes. We should, in fact, detect much wider 

 differences between the dolichocephalous skull of a Swede and 

 the brachycephalous cranium of a Russian ; between that of a 

 Hottentot or an Austral Negro ; between that of a Irokese 

 and a Botocudo ; though all these various tribes are all in- 

 cluded in one race. We are even able to point out greater 

 differences between individuals belonging to the same stock, 

 and it would be easy for me to show by the juxtaposition of 

 the skulls of a Grraubiinden, Zurich, or Bernese man, that 

 these skulls of Swiss tribes differ more from each other than 

 those of the apes we have described. Even an inexperienced 

 individual would find it easier to separate these human skulls 

 in a collection than to assign the above ape-skulls to different 

 species. 



No skeletons of the two species of apes are at my disposal, 

 I cannot therefore furnish you with the measurements of the 

 limbs and other parts. According to Giebel the skeleton of 

 the Cebus is distinguished by greater solidity, that of the 

 large Capuchin monkey being more elegant and slender. This 

 is seen in the ribs, the lumbar vertebrae, pelvis, and sternum, 

 in short, in all parts of the skeleton. Besides this the Oebus 

 has only five lumbar and twenty-four caudal vertebrae, whilst 

 the Capuchin has six lumbar and twenty-five caudal vertebras, 

 corresponding with the greater length of the tail. 



Having no internal parts at hand, I give two brains from 

 Gratiolet^s well known treatise. These brains belong to a 

 simian group of the old world, which has by zoologists been 

 divided into various subgenera. 



The Macacus silenus, which inhabits Ceylon, has a short tail, 

 whilst the Gercojpithecus cethiops, originally probably a native of 

 Senegambia, has a very long tail. I have given also side views 

 of the brains, and have in the first figure turned back the 

 operculum of the posterior lobe, in order to show the transition 

 gyri beneath it. I shall not enter into any details, as even a 

 superficial inspection shows that the form of the brain and its 



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