This is probably the instrument especially made for the Contessina Christina Visconti.
How Many Strads?, Doring, Bein & Fushi, Doring, Bein & Fushi, How Many Strads? (1999 edition), Chicago
". . . originally a bass viola da gamba, is decorated with an armorial shield on front and back, possibly painted after its conversion."
Gold standard, Carlo Chiesa, The Strad, February, 2005, London
Emil Herrmann notes: "1800: brought to England, reduced in size by John Betts and replaced also head.. . . (instrument was enlarged again, proably by Hills)."
The Jacques Français Rare Violins, Inc. Photographic Archive and Business Records, 1844-1998, Archives Center, National Museum of American History, Smithsonian Institution, The Jacques Français Rare Violins, Inc. Photographic Archive and Business Records, 1844-1998, Washington, DC