Turdus boulboul -- Grey-winged Blackbird. Alternate name on piece: Merula boulboul [Grey-winged merula] Layout drawing, birds well finished; 2 notes on form; "M. Boulboul / poecilopteris"; architectural sketches in margin; [Curtis] 8-4768 Artist's name(s): Gould, John; Richter, Henry Constantine.