As for nationality, the gang is apt to be thoroughly unprejudiced and democratic. To be sure, twelve of my sixty-six gangs were all of one nationality. But that is largely because the streets or sections of the city where the boys live are likely to be given up to a single race. Fifty-four of my gangs were of mixed nationality, while in only one was any line drawn at breed or color--“No Jews or Negroes allowed.” Far more than we realize, the boys’ gang is helping out the public school in the great problem of assimilating the diverse races in the United States. Nevertheless, there are some curious differences of nationality in the membership of gangs. Irish boys are especially gangy, with Americans and French a good second. Jews, on the other hand, are conspicuous for their absence. I questioned several Jewish boys, without discovering a single typical gang; and only two of my sixty-six gangs had Jewish members, though Jews are decidedly numerous in the regions from which the boys came. The reader who is interested in race psychology will find food for thought in the differing instincts of Irishman and Jew. There is also some social difference in boys’ gangs. Boys from well-to-do homes are, as one might expect, less gangy than those brought up amid poorer surroundings. In the case of the more fortunate boys, the gang is only one of a number of factors in their social development. But boys from bad, broken, or inefficient homes are forced to provide their own social life, and the gang is their one instinctive reaction to their social environment. Curiously, too, boys from the better class of homes more often form their social groups _de novo_ to suit their individual social needs; while boys whose home training is deficient tend more to become members of gangs already formed. For this reason the permanent and long-lived gangs are apt to be tough, with fixed and dangerous traditions. Thus, while among well brought up boys a gang rarely survives the boyhood of the group which formed it, among delinquents of my acquaintance hardly more than a quarter were original members of their gangs, or could tell how their gangs started. The bad gang, therefore, tends to be a persistent and dangerous institution, taking in new members as the older ones graduate. But the good gang dies young. This circumstance probably accounts in no small degree for the bad odor in which all boys’ gangs are commonly held. _Organization_ In respect to definiteness of organization, there are marked differences in gangs. Some are loosely knit and of short duration; others are select in their membership and rigid in their structure, so that they last through several generations of boys. Some gangs are autocratic, some democratic,--this, naturally, depending largely on the leader.