Botanical name: Thunbergia fragrans Family: Acanthaceae (ruellia family)
Commonly planted in gardens for its attractive white flowers, this slender, herbaceous vine, native to India and Sri Lanka, often establishes itself in thickets, in waste grounds and on roadsides. Thunbergia commemorates Karl P. Thunberg, an eminent Swedish traveller and botanist, who lived from 1745 to 1828; the genus was dedicated to him by the botanist Retz in 1776. Sweet Clock-Vine climbs to a length of 2 meters, or less, and is finely hairy. Its leaves are rather broad, long-pointed, often coarsely few-toothed, slender-stalked, and from 5 to 10 centimeters long. Flowers are white, 2 inches wide and scentless. There has been lot of confusion on why the species name is fragrans. Dr. Roxburgh, who gave the name to this flower, says in his book, Plants of the Coast of Coromandel:Identification credit: K. Karthigeyan & Nandan kalbag
"the plant possesses a peculiar and agreeable fragrance, and the beauty of its flowers, although not fragrant, entitle it to a place in the flower-garden
So, the plant possesses a fragrance, but not the flowers.