Maud Earl painted the depiction of Reginald Cooke’s renowned flat-coated retriever Ch. Wimpole Peter.
This retriever also appears in some of the pedigrees of the foundational goldens.
His sire was Black Drake, but he appears to have been a more typical flat-coat than his father.
Maud Earl was quite the dog painter. She painted dogs in both Britain and the United States. My personal favorite of hers is the depiction of three borzoi heads, which are definitely caricatures of the real thing.
Wimpole Peter can be found behind some of the early Ingestre retrievers. (at least one of which was a registered Flat-Coat before being re-registered as a Golden).
Of course in those years, “Retriever” was the breed, and further designations just “varieties” of Retriever. Interbreeding was common.