Put three images next to each other and you’ll see how differently a siren can be pictured. A Greek terracotta has a human face and a bird’s body. In a medieval manuscript, two forms appear together. An Italian bronze holds up her two tails.
A bird’s body
The Met’s terracotta siren, made around 550–500 BCE, shows the bird-bodied form familiar from Greek art. The museum doesn’t identify her as Parthenope. She’s evidence of how sirens were pictured, rather than a portrait of a named siren. [1]

Wings and fins on the same page
The Queen Mary Psalter, made around 1310–1320, includes a scene with both a bird-siren and a fish-tailed siren. The British Library discusses it in an article on sirens and mermaids. [2]
On this page, one form hasn’t simply replaced the other. They’re there together. It’s a useful detail to keep in mind when telling the story of how the siren’s body changed.

Two tails in bronze
The Met also has an Italian bronze Siren, dated around 1600, who holds up her two tails. Its catalogue discusses different proposals about who made it and for whom. Parts of the sculpture’s history remain uncertain. [3]
Her two tails don’t, on their own, tell us she is Parthenope. They do let us compare her with other two-tailed sirens, including those on printers’ devices.

The figure we chose
Sirendipity’s siren has two tails. The wings, claws and fins found in other images are part of the history around that choice. Looking at each object closely lets us notice differences that a single account of “the siren” can easily miss.