and, in his second edition of the Clouds, he says—

Imitating my images of the eels (ἐγχελέων);

and in his Wasps we find the dative case—

I don't delight in rays nor in ἐγχέλεσιν

And Strattis, in his Potamii, said—

A cousin of the eels (ἐγχελέων).

Simonides, too, in his Iambics, writes—

Like an eel (ἔγχελυς) complaining of being slippery.

He also uses it in the accusative—

A kite was eating a Mæandrian eel (ἔγχελυν),
But a heron saw him and deprived him of it.