266 ORDERS OF BIRDS. 



{Motacilla), and Shrikes (Zanius), with forms allied to the 

 Edible-nest Swifts (Collocalia) and to the Hoopoes (the 

 extinct Zimnatornis). The Palceospiza hella of the Tertiary 

 of Colorado — remarkable for its beautiful state of preserva- 

 tion — appears to be a Finch. Lastly, the Insessorial remains 

 of the late Tertiary and Post-Tertiary deposits present no 

 features of special interest. 



Order VI. Eaptores {Aetomorphm). — All the members of 

 this order are characterised by the shape of the hill, luhich is 

 " strong, curved, sharp-edged, and sha7'p-pointed, often armed 

 with a lateral tooth" (Owen). The upper mandible is the 

 longest (fig. 590, b), and is strongly hooked at the tip. The 

 lody is very muscular ; the legs are rohust, short, with three 

 toes in front and one behind, all armed tuith long, curved, 

 crooked claws or talons (fig. 590, a); the tvings are commonly 

 •pointed, and of considerable size, and the flight is usually rapid 

 and poiverfid. 



Fig. 590.— A, Foot of the Peregrine Falcon ; b, Head of Buzzard. 



The order Eaptores is divided into the two sections of the 

 Nocturnal and Diurnal Eaptores, comprising respectively the 

 forms which fly by niglit and those which fly by day. In 

 the former are only the Owls, and in the latter are the 

 Hawks, Falcons, Eagles, and Vultures. 



As regards the distribution of the Ecqitorcs in time, both 

 the Diurnal and Nocturnal sections of the order seem to 

 have been differentiated in the early Tertiary period; tlie 

 former being represented by the Zithornis vulturinus of the 

 London Clay, a relative of the American Vultures {Cathar- 

 tidce), wliile the Bubo leptosteus of the Eocene of Wyoming is 

 an example of the latter. In the European Miocene we 



