The cult of the Echinocactus Williamsii (peyotl ; mescal) and the remarkable train of phenomena which follow its ingestion have constituted a most fascinating study for many years. Despite the singularity of the symptoms of mescal intoxication, the drug had remained but little known until the treatises of Rouhier and Beringer in recent years made it familiar to us. This present volume, the work of Dr. Kluver, is, however, the only monograph in English on the subject. Within its pages the author has dealt with the broad aspect of the subject; he has written of the rituals and ceremonies with which the native devotes have surrounded this plant, which indeed they have exalted to divine rank. Kluver also deals shortly with the pharmacological aspect of the crude drug and its constituent alkaloids.