What a loss.

From The Book of Lost Books: An Incomplete History of All the Books You'll Never Read by Stuart Kelly (boldfaced emphasis mine):

Aristophanes' plays combine Crates' philosophical speculation with Cratinus' energetic satire. Aristophanes was a very literary comedian, and the loss of The Poet, The Muses, Sappho, and Heracles the Stage Manager not only robs us of examples of the earliest theatrical self-consciousness, but also prevents us seeing, askance, the literary world that indubitably furnished him with ample targets for ridicule (51).

Kelly, Stuart. The Book of Lost Books: An Incomplete History of All the Books You'll Never Read. New York: Random House, 2005.