secretary bird or sagittarius serpentarius, showing nictitating membrane in the eye

accipitriformes ancient antique art artwork aves bird black drawing engraved engraving etching eye eyelid haw illustration magasin membrana membrane nictitans nictitating old palpebra picture pittoresque plica prey sagittariidae sagittarius secretary secretarybird semilunaris serpentarius sketch species tertia third threatened translucent transparent vector vintage white