In one of the later scenes of Arrabal's Viva La Muerte there's a scene in an abattoir where a bull is slaughtered and the animal's testes removed - they are more the shape of a partially-filled weather balloon - rounded (in the sense of elliptical) rather than circular.

Another approach is to look at those beaten gold pieces. Those little moons. There are rows of embossed roundpoints made with a metal punch - there's plenty on the Mold Cape (he finds) - http://news.bbc.co.uk/1/hi/wales/1897131.stm

If anyone can name the Dutch child's nonsense song in Viva La Muerte I'd be very grateful.