66 OBSERVATIONS AND MEASUREMENTS ACADEMY MEMBERS ,M ™°™o£ xxrafc 



Table 52. — Width of the mouth 



Subjects 



Average 



Minimum 



Maximum 



Range of variation in percentage of the average 

 a 



cv 



Members of the Academy 



Old Americans 



92 



5. 66 ±0. 029 



4. 7 



6.7 



35. 34 



0. 414 ±0.021 



7. 31 ±0. 36 



Not old Americans 



48 

 5. 85 ±0.035 



5. 1 



6. 8 

 28. 91 



0. 357 ±0. 025 

 6. 06 ±0. 42 



Old Americans at 

 large (labora- 

 tory series) 



247 



5.37 



4. 5 



6.6 



SO. 10 



DISTRIBUTION 



Old Americans (92) 



Not old Americans (48). 



Percent 



2. 2 



4. 9-5. 1 



Percent 

 7.6 

 2. 1 



6. 2-5. 4 



Percent 



21. 7 



6.3 



5. 5-5. 7 



Percent 

 27.2 

 25.0 



5.8-6 



Percent 



27.2 

 39.6 



6. 1-6. 3 



Percent 



8. 7 

 18. 7 



6. 4-6. 6 



Percent 

 4.4 

 4.2 



6. 7-6. 8 



Percent 

 1. 1 

 4.2 



WIDTH OF THE MOUTH AND AGE 



Members of the Academy 



Old Americans 



Not old Americans 



Old Americans at 

 large (labora- 

 tory series) 



Subjects to 60 years of age, inclusive 



Mean age, years 



Average 



<r 



CV 



Over 60 years of age 



Mean age, years 



Average 



<r 



CV 



55 



52.0 



5. 60 ±0. 034 



0. 372 ±0. 024 



6. 66 ±0. 43 



37 



69. 1 



5. 76 ±0.049 



0. 444 ±0.035 



7. 68 ±0. 60 



22 



51. 7 



5. 83 ±0.044 



0. 308 ±0. 031 



5. 27 ±0. 54 



26 



68.7 



5. 92 ±0.052 



0. 390 ±0.036 



6. 58 ±0. 62 



247 

 37.2 

 5.37 



The mouth width is seen to be about as variable as were the two nasal measurements. 

 In the members of the Academy of more recent derivation it exceeds that of the old Americans, 

 and in both Academy groups it is distinctly superior to that in the old Americans at large. The 

 differences between the members and the outsiders are connected partly with stature, but more 

 so with age; 39 those between the two groups of the members may possibly be accidental, but 

 more likely are connected with the different racial heritage in the two groups. Among the 

 academicians, age influence manifests itself as shown in table 52. 



In both groups in those above 60 the mouth is slightly larger than in those up to 60. The 

 increase in mouth width is observable from birth on throughout life and is an actual growth, 

 though in the aged this may be aided by the flattening of the oral arch due to the absorption 

 of the alveolar processes. 



3« See The Old Americans, pp. 270-271. 



