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MEMOIES OF THE NATIONAL ACADEMY OF SCIENCES. 



8. APPARENTLY NORMAL SKULLS. 



There are 16 skulls which, if never seen in connection with the rest of the collection, might 

 readily be regarded as normal skulls. Taken by themselves, the fact that they are deformed is 

 not obvious; studied along with the rest of the group, where there is every gradation from the 

 most unquestionably flattened to the apparently normal, the observer has no doubt that the causes 

 which operated in distorting the former class have had their effect too in shaping the latter, and 

 lie, feels uncertain where, in any shortened skulls, he is to draw the dividing line between the 

 normal and the abnormal. To what extent do the pillow and cradle of civilization affect the 

 skull? In our great collection of Indian crania, those which are the longest, without obvious 

 artificial deformity, and those which have the best developed occipital shells belong to tribes which 



Fio. 30. Occipital depression, left lateral. 



use no cradle-boards or baby baskets; but carry their children in soft bundles, on the back, in 

 blankets or in frames which present a flexible surface of stretched cloth or buckskin to the occiput 

 of the infant. 



It is evident (see Tables iv and v) that these apparently normal skulls partake fully of the 

 brachycephaly of the whole group. They represent neither the longest nor the shortest of the 

 entire series; their extremes being 78.10 and 91.GG, and their average cranial index (80.94) is but 

 little lower than the average of all (88.47). 



Many craniometricians advise that the deformed skulls like most in this collection should not 

 have their cranial measurements taken or placed on recoid for comparison. Such advice has not 

 been followed here. All that do not show decided post-mortem distortion have been measured. This 

 has been done because of the uncertainty referred to above in distinguishing betweeu the normal 



