466 BRITISH BIRDS. 



Family PELARGIDiE, or HERONS. 



The Herons and tteir allies form a small and isolated family^ which 

 Sclater elevates to the rank of an order under the name of Herodiones 

 (the PelargomorphBe of Huxley). Forbes agreed with this classification, 

 except that he removed the Ibises and the Spoonbills, which he placed 

 in juxtaposition with the Curlews and the Cranes. In the Herons, Storks, 

 and at least one of the Spoonbills, there is only one deep cleft on each 

 side of the posterior margin of the sternum j but in the majority of the 

 Spoonbills, and in the Ibises, there are two notches on each side. The 

 modification of the cranial bones in this family, like that of the Birds of 

 Prey and the Owls, is somewhat variable, the typical desmognathism being 

 occasionally incomplete. In their myology, and in the character of their 

 digestive organs, they agree fairly well together ; but in their pterylosis the 

 Herons are somewhat peculiar, the presence of what are called "powder- 

 down patches " isolating them from all other birds, except some species of 

 Birds of Prey, Parrots, and one or two other genera. 



It has generally been supposed that most of the birds belonging to this 

 family have only one complete moult during the year, which takes place 

 in autumn. All ornithologists admit that the Ibises moult their small 

 •feathers a second time in spring; and there can be little doubt that the 

 special nuptial feathers, such as the elongated scapulars of the Egrets and 

 the crests of the Spoonbills, appear in spring and are lost in the autumn 

 moult. In the birds of all these genera tbe quill-feathers are moulted 

 very slowly, and apparently in pairs, only as they are required, and 

 probably at any season of the year except when the birds are engaged in 

 breeding, in tbis respect resembling the Swifts and the Birds of Prey. 



Their principal external characters are their long legs, and long and 

 powerful bill. The young birds are covered with down, and are able to see 

 as soon as they are hatched, but are comparatively helpless, and are fed by 

 their parents for a considerable time before they are able to leave the nest. 

 The wings are usually long and broad and contain ten primaries, and the 

 tail is short and nearly even. 



This family includes about a hundred and twenty species, and is almost 

 cosmopolitan, except that it is not represented in the Arctic Regions. 

 Thirteen species are European, three of which breed in the British Islands, 

 and tbe rest are accidental stragglers to them, as is also one American 

 species. 



