Some twenty years ago, when few major books of Galen were available in modern English, one of his lesser writings, the treatise Περὶ μαρασμοῦ was published in translation. Even while this translation was in press, Pearl Kibre unearthed in the Vatican Library a text De marasmode secundum sententiam Galieni, which was composed by Bernard of Gordon at Montpellier in the early 1300s and is the only systematic discussion of marasmus in the medical literature for some fifteen centuries after Galen. By further coincidence, these two texts made their appearance just as several historians of science and of medicine were drawing attention to the ancient and medieval interpretations of life as the interaction between ‘innate heat' and ‘radical moisture'—precisely the paradigms in which the concept of marasmus was rooted. In 1974, in a seminal article on the Humidum radicale in thirteenth-century medicine, Michael McVaugh offered a first assessment of Bernard's discussion. His positive appraisal suggested that the text was worth editing and analyzing on its own terms, an enterprise that became more feasible with the recognition of additional manuscripts, references, and implications. A critical and annotated edition is presented here, together with an effort to collate Bernard's treatment of marasmus with his other works, with the teachings of his colleagues, and with the Galenic tradition.