Bird of prey "Accipitres", subdividing this into four genera: "Vultur" (vultures), "Falco" (eagles, hawks, falcons, etc.), "Strix" (owls), and "Lanius" (shrikes). This approach was followed by subsequent authors such as Gmelin, Latham, and Turnton. Louis Pierre Veillot used additional ranks: order, tribe, family, genus, species. Birds of prey (order Accipitres) were divided into diurnal and nocturnal tribes; the owls remained monogeneric (family Ægolii, genus "Strix"), whilst the diurnal raptors were divided into three families: Vulturini, Gypaëti, and Accipitrini. Thus Veillot's families were similar to the Linnaean genera, with the difference that shrikes were no longer included amongst the birds of prey. In addition
What Bird is That? according to their usual habitat. The accompanying text included brief notes on distribution, breeding and behaviour. While initial sales were poor, history tells us that Cayley had accurately discerned a market need and successfully responded to it. During WWII sales accelerated and Cayley’s first collection, reprinted time and time again, eventually became a household name among birdwatchers and the book was recognised as an Australian classic. The original sponsorship of "What Bird is That?" proved a great investment for the Gould League, who benefited from the sale of its numerous reprints and revised editions. By 1960, it was rated the