In fact the speaker had been describing some species of wildfowl

Once I told Thesiger of a cocktail party in London where in a momentary dead silence a voice went on loudly with the last words of a sentence "... and only copulate at two O'Clock in the morning, in running water." "Ah," said Thesiger, "Sabians"; but in fact the speaker had been describing some species of wildfowl.

G. Maxwell, A reed shaken by the wind (1957), 191