The Foot of Cupid is a trademark

Trademark

A trademark, trade mark, or trade-mark is a distinctive sign or indicator used by an individual, business organization, or other legal entity to identify that the products or services to consumers with which the trademark appears originate from a unique source, and to distinguish its products or...

 of the BBC television series, Monty Python's Flying Circus

Monty Python's Flying Circus

Monty Python’s Flying Circus is a BBC TV sketch comedy series. The shows were composed of surreality, risqué or innuendo-laden humour, sight gags and observational sketches without punchlines...

.

It is often seen in the opening animation credits at middle, then at the end of the opening, dropping down on the title and everything around it with a sound similar to that of a short burst of flatulence

Flatulence

Flatulence is the expulsion through the rectum of a mixture of gases that are byproducts of the digestion process of mammals and other animals. The medical term for the mixture of gases is flatus, informally known as a fart, or simply gas...

.

It was based from Agnolo Bronzino's Venus, Cupid, Folly and Time

Venus, Cupid, Folly and Time

Venus, Cupid, Folly, and Time is an allegorical painting by the Florentine artist Agnolo Bronzino. It is now in the National Gallery, London....

, and has been a trademark icon

Icon

An icon is a religious work of art, most commonly a painting, from Eastern Christianity and in certain Eastern Catholic churches...

for the comedy troupe.