DISTRIBUTION OF ANIMALS. 583 



domain, so that no species would be limited to a particular region. The common crow 

 flies at the rate of twenty -five miles an hour ; the rapidity of the eider-duck, Anas 

 mollissima, is equal to ninety miles an hour ; while the swifts and hawks travel at the 

 astonishing speed of a hundred and fifty miles in the same time. It is true that some 

 species have a very extensive range, as the nightingale, the common wild goose, and 

 several of the vulture tribe. The same kind of osprey or fishing- eagle that wanders 

 along the Scottish shores appears upon those of the south of Europe, and of New Holland. 

 The lammergeyer haunts the heights of the Pyrenees, the mountains of Abyssinia, and 

 the Mongolian steppes ; and the penguin falcon occurs in Greenland, Europe, America, 

 and Australia. In general, however, like plants and terrestrial quadrupeds, the birds are 

 subject to geographical laws, definite limits circumscribing particular groups. The 

 common grouse of our own country affords a striking exemplification of this arrangement, 

 as it is no where met with out of Great Britain ; and other examples occur of a very 

 scanty area containing a species not to be found in any other region. The celebrated 

 birds of paradise are exclusively confined to a small part of the torrid zone, embracing 

 New Guinea and the contiguous islands; and the beautiful Lories are inhabitants of the 

 same districts, being quite unknown in the New World. Parroquets are chiefly occupants 

 of a zone extending a few degrees beyond each tropic, but the American group is quite 

 distinct from the African, and neither of these have one in common with the parrots of 

 India. The great' eagle is limited to the highest summits of the Alps ; and the condor, 

 which soars above the peak of the loftiest of the Andes, never quits that chain. Hum- 

 ming-birds are entirely limited to the western hemisphere, where, a particular species is 

 sometimes bounded by the range of an island, while others are more extensively spread, 

 the Trochilus flammifrons, common to Lima, being observed by Captain King upon the 

 coasts of the Straits of Magellan, in the depth of winter, sucking the flowers of a large 

 fuchsia, then in bloom in the midst of a shower of snow. Among the birds incapable of 

 flight, which rival the quadrupeds in their size, the intertropical countries of the globe 

 have their distinct species, presenting similar general features of .organisation, as the 

 ostrich of Africa and Arabia, the cassowary of Java and Australia, and the touyou of 

 Brazil. In the arctic regions, we meet with species peculiar to them, the Strix lapponicus 

 or Lapland owl, and the eider-duck, an inhabitant of the shores, from whose nests the 

 eider-down is obtained. Several families of maritime birds are likewise limited to 

 particular oceanic localities. Approaching the fortieth parallel of latitude, the albatross 

 is seen flitting along the surface of the waves, and soon afterwards, the frigate and other 

 tropical birds appear, which never wander far beyond the limits of the torrid zone. It 

 thus appears, that notwithstanding the great locomotive powers of birds, particular groups 

 have had certain regions assigned to them as their sphere of existence, which they are 

 adapted to occupy, and to which they adhere in the main, though it is easy to conceive of 

 natural causes occasionally constraining to a migration into new and even distant 

 territories. Captain Smyth informed Mr. Lyell, that when engaged in his survey of the 

 Mediterranean, he encountered a gale in the Gulf of Lyons, at the distance of between 

 twenty and thirty leagues from the coast of France, which bore along many land-birds of 

 various species, some of which alighted on the ship, while others were thrown with 

 violence against the sails. In this manner, many an islet in the deep, after ages of solitude 

 and silence, uninterrupted except by the wave's wild dash, and the wind's fierce howl, 

 may have received the song of birds, forced by the tempest from their home, and 

 compelled to seek a new one under its direction. 



There is no feature more remarkable in the economy of birds than the periodical 

 migrations, so systematically conducted, in which five sixths of the whole feathered 

 population engage. In the case of North America, according to an estimate -by Dr. Richard- 



