A mysterious image of a coiled snake has appeared in a 16th century painting of Queen Elizabeth I, the National Portrait Gallery has said. The Tudor queen was depicted with the snake clasped in her fingers in an original version of the work, but it was replaced with a bunch of roses. The paint has deteriorated over the years to reveal the serpent's outline. The painting will go on display at the London gallery on 13 March for the first time since 1921. It will form part of the Concealed and Revealed: The Changing Faces of Elizabeth I exhibition, which...