Atlas de poche des oiseaux de France, Suisse, et Belgique, utiles ou nuisibles, Paris, Librairie des sciences naturelles 1898, France, birds, Switzerland, Belgium, atlases, Circus aeruginosus, A detailed illustration of a harrier hawk, known as the 'Busard harpayé' or 'Buse d'étang.' This bird features a striking combination of rich brown plumage with a lighter, creamy head. Its sharp, piercing eyes and strong beak indicate its predatory nature. The bird stands on a slender branch, showcasing its powerful talons poised as if ready to take flight. The accompanying text identifies its scientific classification, 'Circus aeruginosus,' and notes its belonging to the family Falconidae, emphasizing its significance in the avian world as a migratory species.