Current knowledge
Unidentified
"I believe this is the picture called Nymphs Bathing, now in the collection of the Duke of Orleans", annotation added by Horace Walpole to the corresponding entry in his copy of George Vertue, Catalogue and Description of King Charles I's Capital Collection.. (1757) in the Surveyor's office, St James's Palace.
This work was first listed by Van der Doort as no. 10 in the Long Gallery; then crossed out and replaced there by van Dyck's Cupid and Pysche and added here
Van der Doort 1639
said to be Giulio Romano
Young Neptune (guiding his four sea-horses with a Trident) going through the sea
Sale Inventory c.1649-51
Walpole Society reference (1972):