“In the midst of the fountain of wit there arises something bitter, which stings in the very flowers.”
Medio de fonte leporum
surgit amari aliquid quod in ipsis floribus angat.
Lucretius (-94–-55 BC) Roman poet and philosopher
Book IV, lines 1133–1134 (reported in Bartlett's Familiar Quotations)
Variant translation: From the midst of the fountain of delights rises something bitter that chokes them all amongst the flowers.
Compare: "Still from the fount of joy's delicious springs / Some bitter o'er the flowers its bubbling venom flings", Lord Byron, Childe Harold's Pilgrimage, Canto I, stanza 82
De Rerum Natura (On the Nature of Things)