turity and plasticity in the young of the higher animals. To master the details of a changing environment in the more serious after-life, a vast number of physical and mental coordinations must be learned. This experimental balancing of impulses is play. (3) In following out the special motives which may be found to underly play—to be a cause, the desire to create, to dramatize, to "show off"—nature urges the youth into groups, and by means of the give and take of association stimulates sentiment, imagination, leadership and that expansion of self which comes from the consciousness of participating in a group of which each member is a contributing factor and the rules of which the member obeys because he has helped to make them.
It is needless to contend that the puritanical aversion to play, remnants of which are still extant, is evidence of an antiquated psychology and a partial interpretation of morality and education. One of the encouraging indications of recent years is the general willingness to examine the phenomena of childhood and adolescence in a scientific manner without the bias of a total-depravity doctrine or the opposite dogma of the unconditional goodness of natural impulses. The real problem is now seen to be that of knowing the facts and of directing the raw material of youthful activities in a wholesome way. A resultant of the changed attitude is a keener perception of the claims of childhood outside the conventional fields of kindergarten and school—in the street, in the department store, in the factory, and in the scores of juvenile employments which are annually entered by children leaving the elementary schools. By following the lead of Groos and other writers we can appreciate the implications of the forces which urge boys and girls to play house, soldier and conductor, to build "shacks," or to guard the grocery-comer for the exclusive nightly meetings of "the bunch." If the suggestion of the evolutionists is valid, that the baseball is a rounded missile whose progenitor was the more deadly arrow or spear, we can understand the popularity of the national sport. We can realize the possibilities which are implicit in the rivalries and emulations between gangs from different neighborhoods; and why, if there are no provisions for the safe overflow of the play impulses in a city made for adults and manufacture, trade, and other solemn "business," the legitimate desires of youth will turn to the harmful practises of outwitting the policeman, collecting stolen goods, or imitating the exciting career of the outlaw.
A second consequence of the investigation of play from the genetic standpoint is a keen awakening to the necessity of channeling the imaginative, enthusiastic energies of youth by organizing clubs, scouts and playgrounds under municipal supervision. The capital invested in social centers and playgrounds is the objective testimony to a new direction of public conscience and will. An expression of the public judg-
