Memnon wrote a large work on the history of that city, especially of the tyrants under whose power Heracleia had at various times fallen. Our knowledge of this work is derived from Photius. Of how many books it consisted we do not know. Photius had read from the ninth to the sixteenth inclusive, of which portion he has made a tolerably copious abstract. The first eight books he had not read, and he speaks of other books after the sixteenth. The ninth book begins with an account of the tyrant Clearchus, the disciple of Plato and Isocrates. The last event mentioned in the sixteenth book was the death of Brithagoras, who was sent by the Heracleians as ambassador to J. Caesar, after the latter had obtained the supreme power. From this Vossius supposes that the work was written about the time of Augustus; in the judgment of Orelli, not later than the time of Hadrian or the Antonines. It is, of course, impossible to fix the date with any precision, as we do not know at all down to what time the entire work was carried.

The style of Memnon, according to Photius, was clear and simple, and the words well chosen. The Excerpta of Photius, however, contain numerous examples of rare and poetical expressions, as well as a few which indicate the decline of the Greek language.