These volumes form part of the large international Theophrastus Project started by Brill in 1992 and edited by W.W. Fortenbaugh and others. Together with volumes comprising the texts and translations, the commentary volumes provide a new generation of classicists with an up-to-date collection of the fragments and testimonia relating to Theophrastus (c.370-288/5 B.C.), Aristotle's pupil and successor as head of the Lyceum.

This is the first to appear of the projected volumes of commentary to accompany the texts and translations on Theophrastus of Eresus: Sources for his Life, Writings, Thought and Influence, edited by W.W. Fortenbaugh and others ("FHSG" (Philosophia Antiqua 54); Leiden, Brill, 1992). It covers the ancient secondary evidence for Theophrastus' views on physiology, zoology and botany; the transmission, reliability and doctrinal content of the reports in the text-and-translation volume are all discussed in detail, and general overviews are provided. The commentary is an indispensable accompaniment to the text-and-translation volume, and the two together will be an important resource for students of the history of the biological sciences in antiquity.