[1] The distinction in Greek is between two forms of the preposition εἰς : the headword has εἰς , more common in classical Attic prose, whereas the alternative offered in the gloss is ἐς , which appears in Ionic, in some kinds of poetry, and is apparently more colloquial. There is no difference in meaning.
[2] For this episode see already at delta 243 (and epsiloniota 241 for the proverb arising). The sum of money involved appears variously as ten, fifteen (as here), twenty and fifty talents.
[3] Aristophanes, Clouds 859.
[4] Menander fr.163 Kock.