36 BUREAU OF AMERICAN ETHNOLOGY [bull. 34 



degraded than the Otoini, but nearer the Mexican settlements and in 

 the larger villages drunkenness among them is frequent. 



The Tlahuiltec are very unapproachable, superstitious, and much 

 addicted to drunkenness. While they cling to their ancient style of 

 habitations, costume, and language, their mode of life has lost to a 

 great extent its primitive nature. 



The change from old to modern views and habits, particularly to 

 such as have a bearing on the physical well-being of the Indian, is 

 everywhere slow and tedious. 



IX. PHYSIOLOGY 



The foregoing chapters have touched on the ordinary conditions of 

 life and such of the characteristics of the people of southwestern 

 United States and northern Mexico as are presumably capable of 

 influencing their physiological functions and health. 



Environment has undoubtedly modified the habits of the Indian, 

 but it is a question whether these habits and the effects of environ- 

 ment, so far as not overcome by adaptation, have been powerful 

 enough permanently to change any of the functions of his body estab- 

 lished through ages. The answer is difficult, for there is no certainty 

 as to the character of the environment in which the Indian originally 

 developed and no knowledge as to the nature of his functions when 

 he settled where he is at the present day. Seeking for analogies it is 

 found that numerous whites live in similar climates and that their 

 habits also have been modified by the environment, but thus far 

 without any known important functional modifications. 



From the foregoing considerations it seems that there is nothing 

 in the present conditions of life among the Indians in question on 

 the basis of which important physiological (lifl"erences between them 

 and whites could be expected. There are few prolonged extremes in 

 climate that are not well provided against; there are no protracted 

 periods of undergrade or of high-grade nourishment, or of very excep- 

 tional foods ; and there is no continuous lack of exercise or protracted 

 special exercising of any organ. vShould functional differences of 

 importance appear they are to be regarded as a persistence of the 

 results of past conditions rather than as the outcome of those belong- 

 ing to the present era. 



The physiological and medical studies here presented were untler- 

 taken with the view of recording and analyzing as far as possible the 

 actual conditions among a large group of tribes; but they are not as 

 detailed as could be desired, owing to the vastness of the field. The 

 work consisted in carrying out with due care a limited number of 

 practicable observations, and, beyond this, in utilizing as far as 

 possible any opportunities for gaining knowledge that presented 

 themselves. 



