A revised classification of the naked amoebae is proposed on the basis of a synthesis of many kinds of information presently available for taxonomic purposes above the species level. These amoebae, constituting the subclass Gymnamoebia within the class Lobosea, superclass Rhizopoda, include not only strictly lobose amoebae but also those with more or less filose subpseudopodia produced from a broader hyaline lobe. The subclass is divided into the orders Amoebida, Schizopyrenida, and Pelobiontida, and suborders are recognized within the order Amoebida. Although the Gymnamoebia are undoubtedly heterogeneous and polyphyletic and the proposed classification is intended chiefly as a practical system with a logical basis, there are a few suggestions of natural relationships.