V. Pervigilium Veneris. Cf. Philomela in Parts II and III.
to Part II, lines 99-103 :
428) Quando fiam uti chelidon--O swallow swallow
and to Part III, lines 203-206 :
99) The change of Philomel, by the barbarous king
100) So rudely forced; yet there the nightingale
101) Filled all the desert with inviolable voice
102) And still she cried, and still the world pursues,
103) 'Jug Jug' to dirty ears.
203) Twit twit twit
204) Jug jug jug jug jug jug
205) So rudely forc'd.
Additionally, see also Part V line 356-357 :
356) Where the hermit-thrush sings in the pine trees
357) Drip drop drip drop drop drop drop
As mentioned for line 103 the "twit", "jug" and "tereu" lines were used by Elizabetian poets to represent the song of the nightingale. Tereu is a form of the name Tereus. See Ovid's The Story of Tereus, Procne, and Philomela or our synopsis of the Philomela myth by visiting line 99.