99 



races varying from thirty to the three predominant ones which 

 Blumenbach first clearly pointed out, the Ethiopian, the Mon- 

 golian, and the Caucasian or Indo-European. These varieties 

 merge into one another by easy gradations. The Malay and the 

 Polynesian link the Mongolian and the Indian varieties; and the 

 Indian is linked by the Esquimaux again to the Mongolian. The 

 inhabitants of the Andaman Islands, New Caledonia, New Guinea, 

 and Australia, in a minor degree seem to fill up the hiatus between 

 the Malayan and the Ethiopian varieties ; and in no case can a well 

 marked definite line be drawn between the physical characteristics 

 of allied varieties, these merging more or less gradationally the one 

 into the other. 



In considering the import and value of the osteological differ- 

 ences between the gorilla the most anthropoid of all known brutes 

 and man, in reference to the hypothesis of the origination of 

 species of animals by gradual transmutation of specific characters, 

 and that in the ascending direction : it may be admitted that the 

 skeleton is modifiable to a certain extent by the action of the 

 muscles to which it is subservient, and that in domesticated races 

 the size of the animal may be brought to deviate in both directions 

 from the specific standard. By the development of the processes, 

 ridges, and crests, and also by the general proportions of the bones 

 themselves, especially those of the limbs, the human anatomist 

 judges of the muscular power of the individual to whom a skeleton 

 under comparison has appertained. 



The influence of muscular actions in the growth of bone is 

 more strikingly displayed in the change of form which the cranium 

 of the young carnivore or the sternum of the young bird undergoes 

 in the progress of maturity; not more so, however, than is mani* 

 fested in the progress of the development of the cranium of the 

 gorilla itself, which results in a change of character so great, as 

 almost to be called a metamorphosis. 



In some of the races of the domestic dog, the tendency to the 

 development of parietal and occipital cristse is lost, and the cranial 

 dome continues smooth and round from one generation of the smaller 

 spaniel, or dwarf pug, e.g. to another; while, in the large deer- 

 hound, those bony cristse are as strongly developed as in the wolf. 

 Such modifications, however, are unaccompanied by any change in 

 the connexions, that is, in the disposition of the sutures, of the 

 cranial bones; they are due chiefly to arrests of development, to 

 retention of more or less of the characters of immaturity : even 



