The author informs us in his preface, that his work was intended to take the place of a similar Lexicon by the Grammarian Hyperechius, for such is the true reading, and not Hypereschius, as it stands in the text of Philemon (Suid. s. vv. Ὑπερέχιος, Λέων ; Tzetz. Chil. 10.305). The work of Hyperechius was entitled , and was arranged in eight books, according to the eight different parts of speech [HYPERECHIUS]. Philemon's lexicon was a meagre epitome of this work, the best parts of which he seems to have omitted : it is, however, not without its value in the department of literary history. It is often quoted in the The part of it which is extant consists of the first book, and the beginning of the second, περὶ ὀνομάτων. Hyperechius lived about the middle of the fifth century of our era, and Philemon may probably be placed in the seventh.