2 BUREAU OF AMERICAN ETHNOLOGY [bull. 34 



among others these great helps were partly or wholly lacking; hence 

 the notes for different localities are not of equal interest or extent. 

 The data concerning medical practices, which among the Indians are 

 largely thaumaturgic in character and of minor importance from the 

 medical point of view, are especially incomplete. To acquire a thor- 

 ough understandino; of some of the features of Indian life herein 

 touched on would require unusual opportunities and years of patient 

 labor in a limited field. 



One of the main results of the present studies is the accumulation 

 of evidence that in many points of physiological nature, as well as in 

 those relating to medicine, there is mvich similarity among all the 

 tribes visited. This likeness extends, so far as can be judged from 

 data and observations on other tribes, far beyond the region already 

 outlined. Another point of even greater importance is the growing 

 evidence of similarity, though never reaching full identity, of the vital 

 processes in Indians and whites. 



In elaborating these data the writer has arranged the text by sub- 

 jects rather than by tribes. The report is prefaced with brief notes 

 of a more general nature on conditions which determine the welfare 

 of the native population, as an outline of these conditions is neces- 

 sary to a full appreciation of the physiological and medical studies 

 presented. 



II. GENERAL ENVIRONMENT 



The region inhabited by the tribes to which these studies relate 

 lies between latitude 38° and 18°, west of the Rio Grande and the 

 Mexican Central railway and east of the Rio Colorado and the Gulf 

 of California. Much of this vast area, particularly in the north, is 

 arid, but, on the whole, the aridity decreases from north to south. It 

 is characterized by numerous isolated mountain groups or ridges, in 

 which erosion has carved rugged canyons, some of great depth, between 

 which extend large level plateaus, or llanos." The slopes are usually 

 steep, so that most of the rainfall is speedily drained off through the 

 canyons and narrow valleys. The plateaus, mostly sandy, are cov- 

 ered more or less with grass and other sparse vegetation, but are 

 unfit for cultivation in the absence of artificial irrigation; but the 

 river bottoms everywhere afford rich arable lands. The moimtain 

 summits and the numerous high table-lands are in some instances 

 almost barren, but more often they are covered with stunted oak or 

 cedar. On some of the great mesas, however, particularly in Mexico, 

 beautiful forests of oak and pine extend for many miles. 



a A thorough geographic, geologic, and elimatologie summary of this whole area is wanting. Contri- 

 Initions to this subject, however, will be found in Hayden's, Wheeler's, Emory's, and Powell's, 

 contributions, and in the Pacific Railway Surveys. See N. II. Carton's Catalogue and Index of Con- 

 tributions to North American Geology, 1732-1891, Bulletin 1B7, United States Geological Survey, Wash- 

 ington, 1896. 



