[The nosology of depressions (author's transl)].

The author presents the classical nosology of depressive states, with its five main categories (depression belonging to the manic-depressive psychosis, involutional organic-symptomatic, psychogenic, depressive personality disorder). He comments on the two recent modifications: distinction between the unipolar and bipolar forms, suppression of the category of involutional depression. He presents finally the two modern nosological systems, ICD 9, a relatively traditional nosology, and DSM III whose fundamental principles and categories are discussed.