17th September 1762

Gave to see the Queen's African Ass which was made a present to her by one of our Captins. Its a most beautiful Creatur 6d

Thanks to a knowledgeable reader, I have found this "Creatur"!

It was a female zebra. Some sources claim it was a Quagga (now extinct) but there is a contemporary portrait of her.
This is a print held in the British Museum after a painting by Stubbs

The curator's notes say

"The zebra was kept at Buckingham House and caused great interest. For a contemporary account, see the London Magazine, July 1762; according to a note on an impression of the illustration in the magazine (1862,1011.556), when the animal died it was stuffed and displayed at the Leverian Museum, Blackfriars Road."

Other sources say she lived at Kew and yet more in St James's Park. Perhaps the zebra lived in different places at different times?

For comparison, here is a quagga