The Owls 5 1 r 



are birds of the wooded districts, spending their entire time in trees and 

 rarely if ever coming to the ground to seek for their food. They are very 

 shy, wary birds, flitting incessantly about among the branches in quest of 

 insects, or climbing about the trunks after the manner of Woodpeckers, and 

 prying into every crack and crevice for eggs and larvae of insects as well as the 

 various bark-haunting species. Their nesting habits are similar to those of the 

 Hoopoes, and the nest cavity is said to be in the same ill-smelling condition, in 

 fact, the birds themselves are described by Mr. Ayres as having a peculiarly power- 

 ful and disagreeable smell. The eggs of some of the species at least are said to 

 be white. The birds go about in small, often evidently family parties, and have 

 a harsh, resounding cry, whence one or more are known to the Dutch under the 

 name of Kackela or Chatterer. 



The Purple-tailed Wood Hoopoe (Irrisor mridis) may be selected as an 

 example of the first genus. About fourteen and a half inches long, the upper 

 surface is a glossy metallic green, shaded with bronze on the back, and steel- 

 blue on the crown and nape, while the wings are steel-blue, the primaries with 

 a middle band of white and their coverts white-tipped ; the tail is purplish with 

 violet reflections, the middle pair of feathers unspotted and the others with a 

 subterminal band of white; the under parts are glossy metallic green. In 

 Northeast Africa and West Africa this species is replaced by a closely allied 

 form (/. erythrorhynchus] which differs mainly in having a steel-green tail which 

 shows scarcely any violet or purple reflections. 



In the Straight-billed Wood Hoopoes (Scoptelus) the bill is generally much 

 less curved than in the others, while in the Scimitar-billed Wood Hoopoes (Rhino- 

 pomastus) the bill is very much curved. In all the plumage is more or less 

 steel-blue or purple. 



THE OWLS 



(Suborder Striges) 



The Owls were formerly, and indeed by some authorities are still, regarded 

 as being most closely related to the diurnal birds of prey, or to the Hawks and 

 Eagles (Accipitres), the two, it is assumed, constituting groups of coordinate 

 rank, but the conviction has been growing of late years that the Owls are entitled 

 to a higher rank and that their relationship is rather with certain "Picarian" 

 groups, especially with the Goatsuckers. Beyond the fact of their raptorial habits 

 and the shape of their bills and feet, which have largely resulted from these habits, 

 there is really very little to be said regarding the kinship between the Owls 

 and the Hawks and Eagles, and it is held that they could not have been derived 

 from a common stock. For instance, the ambiens muscle, which is regarded as 

 of high taxonomic importance, is present in all Accipitres and absent in all 

 Owls, and Gadow, whom we are largely following, urges the impossibility of the 

 Owls once possessing and subsequently losing this muscle. Other anatomical 

 differences are the basipterygoid processes, present in all Owls and absent in 

 all Accipitres except in the American Vultures and the Secretary-Bird, which 



