The nymph Echo was in love with the beautiful youth Narcissus, who rejected her cruelly. The goddess Nemesis punished Narcissus by making him fall in love with his own reflection, seen in a pool. Echo died, leaving only her voice, and Narcissus died because his love remained unrequited.
The lower of the two nymphs in the trees is probably Echo. The reclining nymph at the bottom, who was originally draped, seems to have been repainted as a nude in the 18th century.
The story comes from Ovid's 'Metamorphoses' (Book 3) and was frequently painted, but this is Claude's only known treatment of the subject. It is also one of only two paintings recorded by him as having been made for an English patron who, unfortunately, has not been identified.