360 BUREAU OF AMERICAN ETHNOLOGY [Bull. 182 



more than breadth, resulting in a nose that is not only much larger, 

 but relatively narrower than that of the earlier population. Palatal 

 dimensions show the greatest increase in size (about 12 percent) 

 but only a slight change in shape. It is unfortunate that the damage 

 to the landmarks determining the facial triangle is so common, 

 for the variations in the facial components suggest interesting changes 

 in prognathism. In view of the increase in other craniofacial dimen- 

 sions, the decrease in the height of the mandibular symphysis seems 

 of considerable significance. This decrease may have been associated 

 with the diminished chewing stresses resulting from a softer diet. It 

 does not seem to have been associated with any change in the occlusal 

 pattern or an increase in frequency of overbite. It is notable that in 

 the females, the facial, nasal, and orbital modules are about the same 

 in both populations. The cranial and palatal modules are larger in 

 the Clarksville females. As in the males, the face and its components, 

 while about the same size, are shorter and broader. 



A number of differences appear in the postcranial skeletons (table 

 5) . As previously noted, the long bones of the male Clarksville skele- 

 tons seem to be, on the average, about 3 to 4 percent longer than those 

 of the Tollif ero skeletons, while the average lengths of the long bones 

 of the female skeletons remain unchanged. Yet the body propor- 

 tions, reflected in the radio-humeral, tibio-femoral, and intermembral 

 indices, are about the same, and accord well with the indices from 

 other Indian groups (see table 7) . Whereas the cranial module shows 

 an increase of 2.6 percent in the Clarksville males, increase in femoral 

 length is 4.6 percent. Possibly, then, the postcranial skeleton is more 

 susceptible to variation in size than the skull. At any rate, it would 

 seem that while an increase in caloric intake may have increased 

 height, it did not greatly affect the relative proportions of the limbs.^ 

 Although, as noted, the Clarksville males seem to have been somewhat 

 taller than the earlier Tollifero males (table 7), increase in size again 

 appears to have been restricted to the men, for long bone lengths in 

 the women of the two groups seem to have been about the same. 



It would seem that two agencies of change are involved. The in- 

 crease in cranial and postcranial size, seen only in the men, is more 

 likely to be due to dietary change than to change in genotype. 

 Changes in facial proportion, seen in both men and women, may be 

 genotypic. Consideration of both males and females is necessary to 

 distinguish the roles of these two factors. 



The male tibiae of the Tollifero skeletons show one feature calling 

 for special comment : Except in two individuals — the two brachycranic 



■Roberts (MS., 1953, p. 114) notes an Increase In the tibiofemoral index with ambient 

 climate, interpreting this as a thermoregulatory device. If this is so, It is possilile that 

 an increase in hent production, accompanying Increased caloric intake, could produce an 

 analogous effect on limb proportions. 



