374 ITS HABITS. 



Swedish soil. When in northern Dalecarlia, on the 17th 

 of April, 1851, the ground being then deeply covered with 

 snow, numbers passed over our heads. During migration, 

 these birds always fly in two lines, which in front meet in 

 an acute angle, thus forming a figure somewhat resembling 

 the Greek letter Y, which indeed from this very circumstance 

 is said to have derived its shape. One of the company 

 therefore always flies in advance of the rest and thus consti- 

 tutes the vertex of the angle ; and if the movements of the 

 flock are watched, it may readily be observed that when this 

 individual becomes fatigued with being the first to cleave the air, 

 it falls to the rear, and leaves the next in succession to take its 

 post. It has been noticed, moreover, that when the cranes, 

 on these their migratory flights, meet with a lofty hill, they 

 utter shrill cries, appear anxious and restless, and fly without 

 any kind of order. Gradually, and each for itself, they now 

 ascend spirally, until such time as they have attained to a 

 sufficient height to pass over the eminence, when, assuming 

 their original formation, they proceed slowly on their course. 

 At times their flight is so very high, that notwithstanding each 

 individual occupies a considerable space, the birds themselves, 

 though heard in the air, are not perceptible to the naked 

 eye. Their shrill, loud, and trumpet-like note is audible far 

 and near, and if at a short distance is almost deafening. 

 Their voices are rendered the more powerful, owing to the 

 peculiar conformation of the wind-pipe, which forms several 

 curvatures in the breast-bone, before descending into and 

 joining the lungs. 



The crane is one of the tallest and most stately birds in 

 Scandinavia. When it stands upright, it reaches to the 

 breast of a man, and the wings, when extended, are about 



