Good afternoon! This is, of course, a unicorn. But you showed the tail incorrectly.
Unicorns have a different tail than horses. It's more like a zebra's. The crown wasn't always there. On the English coat of arms, the unicorn had a tassel at the end of its tail that was always identical, and very similar to the one painted on the ship. The tassel at the end of the tail consisted of three strands, the top strand being the longest, and the lower strands each shorter than the one before. Perhaps De Velde simply didn't have the space or the inclination to paint the tail in detail, and only had the energy for the tassel.
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