71 



that from dol'cboceplialy to bracliyceplialy a series of individual vai-iations 

 Avill be found closing- np apparent gaps. I am far from denying that bra- 

 cliy cephalic or dolichocephalic crania may be found to be characteristic of 

 races restricted to a limited area or uniform conditions, but that craniology, 

 any more than oology, is an exact science, seems yet to be proved. That 

 a race can be identified by cranial characteristics, though often assumed, 

 has never been satisfactorily established, and the practice of characterizing 

 a people from the examination of half a dozen skulls, as has occasionally 

 been done, seems little short of absurdity. I cannot i-efrain from siiggest- 

 ing that much of the apparent confusion in certain departments of American 

 archaeology is likely to be cleared up when its full measure is allowed to the 

 factor of individual variation. When such extremes in difference of form, 

 for instance, as 199™" and 165""", with respective breadths of 137'"™ and 

 144"'™, are on record among Eskimo crania, and by no means very excep- 

 tional, a little hesitation in accepting world-wide theories, based on a few 

 narrow or broad skulls of a given people, seems not unreasonable. 



C— THE HUNTING PERIOD. 



With the ability to kill, by means of bone weapons, and aided by some 

 kind of skin canoes, not only fish from the shores, but sea-animals, and 

 even birds, many new instruments were required. ]\Iany new wants and 

 applications of material sprang into being. To utilize the results of the 

 chase, many new contrivances were necessary. With this expansion in 

 their powers, and this change in the habits of the aborigines, the stratum 

 which I have termed the Mammalian layer began to be deposited. This 

 was eminently an epoch of hunters. 



The Mammalian layer has been recognized wherever we have made 

 excavations. It attains a varied thickness in different localities, due to 

 differences in population and abundance or scarcity of the animals hunted. 

 Many refuse or kitchen heaps were entirely deposited during this epoch. 

 It is evident that the population, whose increase had begun during the last 

 period, now that the means of sustenance were so greatly enlarged, might 

 expand until the food supply and consumption were again in equilibrium. 



