Clytie - British Museum, London, UK - Epic Beings and Creatures on Waymarking.com

The plaque, on the pedastal on which the bust of Clytie sits, tells us:

Clytie
Roman, about 40 - 50 AD
Said to have been found near Naples
From the collection of Charles Townley

The British Museum website tells us:

Clytie was a character in Greek mythology who became jealous of her lover, the sun god Apollo. To punish her, he transformed her into a sunflower so that she would always face towards him in his daily journey across the skies. The subject of Clytie, normally depicted as the head of a woman emerging from a sunflower, was popular among both classical and neo-classical sculptors.

Another page on the museum's website tells us about the bust:

Marble portrait bust of a woman, possibly the younger Antonia. Long identified as the nymph Clytie.

Purchased in Naples in 1772 from the Principe di Laurenzano, and known as 'Clytie' after the nymph turned into a flower for unrequited love of the sun-god Helios, this bust became Townley's favourite sculpture; it was the only marble he took with him when forced to flee his house during the Gordon Riots of 1780.

The name, if inaccurate, is suitably romantic. It is difficult to reconcile the subject's sensual appearance with its modern identification as the younger Antonia (36 BC-AD 38), daughter of Mark Antony and mother of the Emperor Claudius. Jucker's publication of the bust in 1961, enthusiastically endorsing a Claudian date, was much criticised. Several scholars have since claimed 'Clytie' as an eighteenth-century rococo work.

The marble is probably Parian, and if so it must have been quarried in antiquity, since the underground quarries were not again worked until the nineteenth century. The finish on the underside of the lotus leaves, which retain traces of encrustation, also speaks for an ancient origin. However, it is likely that much of the surface of the portrait was reworked to enhance its erotic appeal. The model for this transformation of Roman matron to nymph may have been the 'Flora Farnese', a colossal restored figure celebrated from the sixteenth to the late eighteenth centuries for its erotic associations.

Originally the subject may have worn a heavier and less revealing tunic, such as that worn by an unknown Neronian woman, portrayed in a marble bust now in Sir John Soane's Museum, London. Doubted by those who would have 'Clytie' a forgery, this portrait resembles the more extravagant representations of women at the courts of Caligula, Claudius and Nero.

The extent to which its transformation enhanced 'Clytie's' appeal is demonstrated by its appearance in gems, some of which may have been engraved before 1774 while the portrait was still in Italy, in cameos produced in the 1850s and 1860s, in G. F. Watts's unclothed marble version of 1867, in porcelain figures made by the firm of Copeland from 1855, and in the popular British Museum replicas on sale today.

The Urban Dictionary website tells us about Clytie:

There was once a Nymph named Clytie, who fell in love with Apollo as he drove his bright chariot through the skies. She gazed at him as he rose in the east attended by the rosy-fingered Dawn and the dancing Hours. She kept watching as he climbed high into the skies. She looked on in wonder in the waning light as he guided his steeds to the many-colored pastures where they fed all night on ambrosia.

But Apollo did not see Clytie. He rather, fell in love with her sister, the White Nymph Leucothoe. She fell into a great depression and was full of grief.

Night and day Clytie sat weeping. She did not eat, drink or sleep--but watched Apollo as he moved across the heavens.

The gods took pity upon her. Her body rooted to the ground--green leaves appeared where her arms and hands once were. Her lovely face was concealed by tiny flowers, sweet with perfume. Her love for Apollo never waned. Even to this day she turns her flower face toward the sun--following its rise and decent across the skies.

But men no longer call her Clytie, rather she is known as the Sunflower.