This volume of Alcan's monumental treatise on psychology is divided into two parts, the first dealing with the general functions of organization and the second with the general laws of mental activity. Piéron discusses attention, its evolution and mechanism, habitude and memory. Association of ideas is treated by Delacroix, schematization by d'Allonnes, and symbolization by Dumas. The disrepute into which the association of ideas has fallen is reflected in the brevity of that section. In the second part of the volume Blondel points out the distinction between normal and pathologic automatism necessitated by the work of the psychiatrist de Clerambault, unfortunately recently deceased. Janet summarizes again his illuminating studies on psychologic tension and its oscillations, so neglected in these days of outrageous symbolization. The volume terminates with studies of mental activity, intellectual work, fatigue and sleep; it is better edited than the previous ones.