98 ALE& HRDLIKA 



Months Years 



Lateral Incisor, upper 8-11 Median Incisor, lower 5-8 



Lateral Incisor, lower 12-15 Median Incisor, upper 5-8 



First Molar, upper 9-21 Lateral Incisor, lower 6-10 



First Molar, lower 12-21 Lateral Incisor, upper 6-10 



Canine, upper 16-24 Anterior Premolar, upper 7-14 



Canine, lower 16-25 Canine, lower 8-14 



Second Molar, upper 20-36 Anterior Premolar, lower 8-15 



Second Molar, lower 20-36 Posterior Premolar, upper 9-15 



Posterior Premolar, lower 9-15 



Canine, upper 9-16 



Second Molar, lower 10-17 



Second Molar, upper 10-17 



Third Molar, lower 15-30 



Third Molar, upper 17-30 



The pubic articulation shows important changes with age. 1 

 A valuable indication as to advancing age is furnished to us by the 

 wear of the teeth. 2 In Whites this seldom commences before the thirty- 

 fifth or is marked before the fiftieth year of age, and in many individuals 

 of the more cultured classes it may remain slight up to old age; but 

 among grain-eating, primitive peoples, such as the American Indians, 

 wear may commence even before the adult life has been reached, be 

 very marked at fifty, and reach an extreme grade after sixty-five. 

 Partial wearing, due to peculiar habits, has of course but little value 

 in this connection. 



The obliteration of the cranial sutures has long been relied upon as a 

 help in estimating the age of the subject, and is useful when taken 

 conjointly with other characters. Under normal conditions, i. e. in 

 subjects who have not been affected by rickets or other generalized 

 pathological processes, synostosis of the bones of the vault does not 

 commence until well after adult life has been reached, and in some 

 individuals some or all of the bones of the vault may remain free until 

 advanced age. On the average, however, we may expect to find some 

 traces of synostosis ventrally about the thirtieth, and dorsally about 

 the fortieth year of life. In view of the difficulties of a proper endos- 

 copic examination, the dorsal signs of obliteration are the only ones 

 with which the anthropologist under ordinary circumstances needs to 

 concern himself. The obliteration here may begin in the posterior 



1 See Todd (T. Wingate), "Age changes in the Pubic Bone," Am. J. Phys. An- 

 throp., 1920, III, No. 3, 285. 



2 See Broca (P.), Bull Soc. d'Anthrop. Paris, 1879, S. 3, II, 342; Instructions 

 craniolog., etc., 1875, 132. 



