LECTUEE V. 119 



we must bear in mind that, next to the skull and brain, the 

 skeleton of the trunk and limbs demands our attention, as the 

 relative proportion of the several regions of the body entirely 

 depends upon the skeleton. 



Thus, when we learn that certain tribes of South America, 

 e. g. the Quichuas inhabiting the plateaux of the Andes, are 

 distinguished by an extraordinary development of the thorax, 

 giving to these people a pecuHar aspect, there is good reason 

 for especially remarking the structure of the vertebral column, 

 the ribs, and the sternum, as it may be assumed that charac- 

 teristic differences in this respect 7nay occur in various races. 

 This very instance, however, shows how careful we must be in 

 at once assigning plausible causes for such peculiarities. " The 

 Quichuas," it was said, " live upon the plateaux of the Cordil- 

 leras, in a comparatively rarefied atmosphere. They are like 

 all mountaineers, agile, ascend mountains without much fatigue, 

 and experience no difficulty in breathing, such as is felt in as- 

 cending Mont Blanc. It is not surprising that their chests have 

 gradually expanded and acquired a larger volume, since they 

 have to inspire a larger volume of rarefied air than the inhabit- 

 ants of the plains, in order to obtain an equal amount of 

 oxygen." The conclusion is, in point of fact, unobjectionable ; 

 but unfortunately, nature breaks the whole chain of reasoning 

 by placing in the Siberian plains, along the shores of the 

 Arctic Sea, populations whose chests are not less developed 

 than those of the Quichuas. And thus it is with many other 

 peculiarities attributed to climate, mode of hfe, and other in- 

 fluences ; for we find, on closer examination, that peoples 

 living under entirely different external influences present the 

 very same peculiarities. 



As already stated, the pelvis is the part which most cor- 

 responds to the skull, and by means of which we may most 

 reasonably hope to arrive at some conclusion as regards ethnic 

 peculiarities. It is composed of several bones grown together 

 into one piece in the adult, but separated by sutures up to the 

 seventh year. These bones have received the names of the 

 iliac, ischiac, and pubes ; they form a kind of ring, closed 

 in front by fibrous cartilage, and behind, by the broad and 



