T HIS STUDY encompasses the names of some six hundred adolescent boys' clubs in Brooklyn, New York. These clubs are formed by boys who are associated in school or in a neighborhood. When the members are in the early teens, the activities of the clubs are mainly athletic; teams are put on the field to suit the seasons. Thus a large number of these clubs are called 'Athletic Clubs,' or, more commonly, 'A. C.'s'-e.g., Triangles A. C. and Avons A. C. (The plural forms are remarked on below.) In the later teens life becomes more complex and less stern; the 'Social and Athletic Club' comes into being, this term being shortened to 'S. A. C.,' as in Blue Sox S. A. C. Among the club names collected the predominant connotations are of power, speed, and aggressiveness, with sinisterness as a muted countermelody. The most popular source of such names is the animal world. Thence are found: