The influence of American environment upon the descendants of immigrants increases with the time that the immigrants have lived in this country before the birth of their children. The differences in type between the American-born descendant of the immigrant and the European-born immigrant develop in early childhood and persist throughout life. Among the East European Hebrews the American environment, even in the congested parts of the city, has brought about a general more favorable development of the race, which is expressed in the increased height of body (stature) and the weight of the children. There are not only decided changes in the rate of development of immigrants, but there is also a far-reaching change in the type--a change which cannot be ascribed to selection or mixture, but which can only be explained as due directly to the influence of environment. We are, therefore, compelled to draw the conclusion that if these traits change under the influence of environment, presumably _none of the characteristics of the human types that come to America remain stable_.[49] A very similar result has been reached by Dr. Fishberg in his study[50] of the Jews in America, in which he found that the physical features of the Jews in the United States are changing considerably as the result of change in social elements. Because of lack of scientifically established data pertaining to the physical change of Japanese descendants in America, we forbear from making any bold assertion on that topic. Yet, even to the casual observer, it seems almost undeniable that American-born Japanese children are fast departing from the type which their parents represent, thus corroborating the truth discovered by scientists. The Japanese Educational Association of San Francisco once conducted an extensive physical examination of Japanese children in twenty different grammar schools in California, and found (1) that they are generally superior in physical development to children of corresponding ages in Japan; (2) that in height they are from one to two inches taller than children in Nippon; (3) that in weight they are from three to seven pounds heavier; (4) that they have fairer skin when compared with that of their parents born in Japan; (5) that their hair is dark brown and not jet black, as is that of their parents; and (6) that their general posture is much better than that commonly seen among the children of Japan.[51]