Valmiki Ramayana Kishkindha Kanda Sarga 28 Shloka 52

निलीयमानैः by the resting, विहगैः by birds, निमीलद्भि closing, पङ्कजैः च by lotuses, विकसन्त्या by blooming, मालत्या च by Jasmines also, रविः Sun, अस्तंगतः has set, ज्ञायते is understood.

'The time of the setting Sun (as he remains invisible the whole day) is known only by the birds reaching out to their dwellings for rest, and by the closing of lotuses and blossoming jasmines.