464 BUSTARDS, THICKNEES, AND CRANES. 



ancestral stock from which originated the rails, the Limicolce, and most of the other 



birds treated in this chapter. It will, however, scarcely support his opinion that 



the herons are likewise descended from the cranes, seeing that a meinber of the 



latter existed in the London Clay, belonging to the lovrer part of the Eocene 



period; while it is scarcely likely that the cannon-bone of a heron could have 



been dferived from that of a crane. 



Although the members of the family have been arranged under 

 True Cranes. , *^ '^ 



several genera, it seems on the whole preferable to include all but the 



crowned cranes in the typical genus (Gtus). In the ordinary cranes the long and 

 straight beak is of moderate length, compressed and pointed, with the nostrils 

 placed in a groove near the middle, and partially closed behind by membrane ; the 

 wings have the third quill the longest ; a large part of the tibia is bare ; the front 

 of the metatarsus is covered with scutes ; and the toes are short, with blunt nails. 

 Generally there is a naked region about the eye and the base of the beak, while 

 occasionally the entire head may be devoid of feathei*s. They are birds of large 

 size, with the plumage either grey or white; and the elongation of the inner 

 secondaries into a kind of false tail, gives them a peculiarly graceful appearance. 

 Inhabiting extensive plains "and swamps, and endowed with a powerful and long- 

 sustained flight, most cranes are in the habit of performing migrations of great 

 length. The windpipe being lengthened and arranged in coils within a cavity in 

 the breast-bone enables them to utter, when alarmed or on the wing, a loud 

 trumpet-like call, which is often audible at a distance of a couple of miles. 

 Terrestrial in their habits, — it is said never perching on trees, — all the cranes 

 build on the ground; their huge nests being placed in swamps, and the two or 

 occasionally three eggs having a greenish ground more or less spotted with 

 reddish. 



^ The common crane (G. cinerea), which some three centuries ago 



Common Crane. . . . . , ... 



nested in the British Islands, where it is now but a rare visitor, is 



the typical representative of the genus, and is characterised by the moderate 



length of the beak, which is high and sloping at the base, and straight in its 



terminal half, by the naked forehead, cheeks, and crown, and the general grey hue 



of the plumage. The naked part of the crown is reddish, the sides of the face and 



neck are white, and the elongated secondaries black. Young birds are nearly 



uniformly coloured. In length, full-grown specimens measure from 43 to 48 



inches. The crane is widely distributed over Europe and Central and Northern 



Asia, visiting India, Persia, South China, and Northern Africa in winter, and 



passing through Japan on its migrations. Its breeding-range extends from the 



Arctic Circle in Western Siberia, to Italy and the Danube Valley. In North 



America this species is represented by the brown crane (G. canadensis). Cranes 



usually reach their breeding-grounds in Central Europe from the south at the end 



of March or April, while a month later they arrive in the Arctic regions. At all 



times gregarious, they migrate in vast flocks, which fly during the day at a great 



height in the air in a V- or W-shaped formation, each bird having its long legs 



stretched out behind. Writing of the flight of the American species, Dr. Newberry 



observes that, under the orders of an experienced leader, "each bird keeps his 



place in the ranks ; the advancing column now rides higher over some suspected 



