HEDLicKA] PHYSIOLOGICAL AND MEDICAL OBSERVATIONS 99 



8 (lays) there were as yet no permanent bicuspids; while all eight 

 were present in the two Pima girls of 12 years and 9 months and 13 

 years of age. 



Of the second permanent molars, which appear in whites during 

 the fourteenth year (D.), both lower and left upper were already 

 present in a Pima girl of 10 years and 8 months, the left lower (just 

 broken through) in one of the twin girls (of 12 years 1 month and 8 

 days) and the lower right in the other, while all four were out in the 

 girl of 12 years 9 months and 13 days. 



The following is a brief resume of second dentition : 



The incisors appear in the Pima at about the same age as in whites, 

 and the same statement is probably true %vith regard to the perma- 

 nent first molars and both bicuspids. 



The canines seem to appear somewhat earlier in the Indians than in 

 the whites, but there were not enough cases in the series to decide 

 this point. 



The second molars apparently erupt earlier in the Pima than in 

 white children. 



The shedding of the teeth is dealt with in the detail tables in the 

 Appendix. 



The subject of dentition will be considered again in connection 

 with the second series of cases, in wliich the children whose exact age 

 could not be ascertained are arranged according to stature. 



Locomotion and speech. — Sitting: This particular investigation 

 relates to the period at which the Indian child is able to sit without 

 support. From the data gathered it appears that this period is the 

 latter part of the eighth month among the Pima and during the ninth 

 month among the San Carlos Apache. The difference between the 

 tribes is undoubtedly due to the greater bodily freedom enjoyed by the 

 Pima cliild, which is not confined to a cradle board like that in use 

 among the Apache. 



Crawling: This follows soon after the cliild is able to sit alone, or 

 from about the ninth month. 



Standing: The ability of the infant to stand while holding to some 

 support manifests itself very nearly at the same time as the ability 

 to sit without assistance and to crawl. The ability to stand freely 

 was recorded in all the Apache children of 14 months or older and in 

 all Pima of 15^ months (no subjects between 12^ and 15^ months 

 were examined). 



Walking: In both tribes the acquirement of the power to walk is 

 nearly contemporaneous with the ability to stand freely, soon after 

 the child is 1 year old. It appears that all the healthy Apache as 

 well- as the Pima children of 15 or 16 months can walk alone at least 

 a few steps and that all run about quite freely before the age of 2 

 years. 



