120 BIRDS' NESTS 



or other masonry. Hoopoes do not excavate the nest 

 hole, but they select one, frequently in a willow tree, 

 and in it often form a slight nest of straws, roots and 

 bits of dry cow-dung, but at other times lay their eggs 

 on the powdered wood alone. The nests of these 

 birds are perhaps the foulest and most evil-smelling 

 avine residences throughout the entire class. It is 

 worthy of remark that the male feeds the female 

 throughout the period of incubation, she rarely leaving 

 her charge, in this respect resembling the Hornbills, a 

 group to which the Hoopoes are thought by some 

 naturalists to be closely allied. Those beautiful 

 birds the Rollers (Coracid^) are typically breeders in 

 holes in trees, often annexing one made by a Wood- 

 pecker, where the eggs are deposited upon the 

 powdered wood at the bottom. When a hole in a 

 wall or bank, or a crevice in a rock is selected, the 

 bird apparently constructs a slight nest of dry grass, 

 roots, twigs, and a few feathers — possibly the relics 

 of the nest of some previous tenant of the place. An 

 Ethiopian species, Coraciascaudatus, generally chooses 

 a hole in a baobab tree for a nesting place. Some of 

 the Swallows also resort to holes in trees (often 

 deserted ones of Woodpeckers) for nesting purposes, 

 such as Tachycincta albiventris, and certain species 

 in the genus Progne. 



We now pass to the consideration of those species 

 that conceal their nests, not universally, but more or 

 less frequently in holes in timber. Some of the most 



