136 ROBERT BENNETT BEAN 



The eruption of the teeth begins later in the Indians than in 

 the whites, and ends earlier. The teeth of the Indians erupt more 

 promptly than those of the whites and the canines, second and 

 third molars erupt earlier in the Indians than in the whites. 



To test the relative precocity of the Indians, I have calculated 

 the average age of all the Indian, Filipino, German and American 

 children and the average number of teeth at all ages in all the 

 groups. The ratio of the age to the number of teeth erupted 

 in the order of precocity, is shown below: 



Age: teeth Age: teeth 



(1) Indian girls 100: 176.5 (o) German girls 100: 167.0 



(2) Filipino girls 100:175.0 (6) Indian boys 100:153.6 



(3) Filipino boys 100:170.3 (7) American boys 100:153.0 



(4) American girls 100: 170.0 (8) German boys 100: 150.0 



The Indian girls are the most precocious girls, and the German 

 boys are the most backward boys. The Filipino boys are the 

 most precocious boys, and the German girls are the most back- 

 ward girls. The German boys and girls are the most backward, 

 the American boys and girls are next to the most precocious. 

 The girls are more precocious than the boys, but the difference 

 is not great among the Filipinos and is greatest among the 

 Americans. 



The ratio of the groups when both sexes are combined is: 



Age: teeth Age: teeth 



(1) Filipinos 100: 172.6 (2) Indians 100: 165.05 



(3) Americans 100:161.5 (4) Germans 100:158.5 



The Filipinos are the most precocious, the Germans are the 

 most backward, and the Americans and Indians are between the 

 other two, the Indians more like the Filipinos and the Americans 

 more like the Germans. The Indian women have a greater 

 precocity than the Filipinos, and the Indian boys are almost 

 exactly like the German and American boys. 



Boas (6, 7, 8) and Boas and Wissler (9) have made reports as to 

 the eruption of the pernmnent teeth in American whites but their 

 work has been inaccessible to me, and what I give is based on 



