12 BUREAU OF AMERICAN ETHNOLOGY [BI-U..X* 



although their application may prove arduous and is not certain of 

 affording satisfactory results. 



A geologically ancient bone may be safely expected to show some 

 degree of infiltration and replacement of its constituents by mineral 

 matter, while modern bones are generally little changed: yet there 

 exist in some localities conditions which greatly retard or facilitate 

 the processes of mineralization, so that ancient bones may show I nit 

 little evidence of fossilization, while, on the other hand, undoubtedly 

 recent bones may have undergone decided change. The latter con- 

 'dition is far more frequent. There is a possibility that the kind or 

 the degree of the change may make it practicable to distinguish 

 Ixjtween recent and ancient fossil ization; but there are as yet no 

 satisfactory means of testing this matter. 



Somatologically, the bones, and particularly the skull, of early man 

 may be confidently expected to show some differences from those of 

 modern man, especially in the direction of lesser differentiation. 

 Unfortunately the knowledge of the osseous structures of early man 

 in other parts of the world is still meager, and this lack of informa- 

 tion is felt very keenly. We do not know as yet whether the human 

 beings of the geological period just before the recent differed so 

 from the present man that even the extreme individual variations 

 in the two periods (the most advanced evolutionally in the old and 

 the least advanced among modern individuals) would stand appre- 

 ciably apart. Very likely they overlap and dovetail considerably. 



Yet the difficulties which may attend the separation on the morpho- 

 logical basis of ancient from recent man should not be insuperable. 

 Tf a find should consist of a series of well-preserved skulls or skeletons 

 geologically ancient and of a similarly well-preserved series of skulls 

 or skeletons of recent man, it is the firm conviction of the writer that 

 in a large majority, if not in all, of the cases, their separation would 

 be practicable. The greater the number of male adult normal, and 

 in no way deformed, crania in each find, the easier it would become to 

 make the necessary distinctions; and it may be safely assumed also 

 that the greater the separation of the two groups in time the more 

 distinct would l>e the somatological differences. 



There is no such thing as absolute stability in any human struc- 

 ture. Every organic feature, of whatever consistency or importance, 

 is the result of all the factors by which it was affected. With the 

 skeletal parts by far the strongest of these factors, in itself a very com- 

 posite one, is the potentiality of heredity, next to which in impor- 

 tance comes habitual muscular action, particularly muscular use due 

 to long-established habits of whole groups of people. Heredity, how- 

 ever, especially in so far as it applies to the latest acquired charac- 

 teristics of the skeleton, is subject to incidental irregularities as well 

 as to gradual modifications. IIal>its of muscle action, on the other 



