CRANES. 



353 



table substances. Their note is loud and sonorous, but harsh. During their 

 migrations these birds always fly in two lines, which in front meet at aiTacute 

 angle, thus forming a figure somewhat resembling the Greek letter 7, 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 by 

 being the first to cleave the air, it falls to the rear, and leaves the next in suc- 

 cession to take its post. It has been noticed, moreover, that when the cranes 

 in these their migatory flights meet with a lofty mountain, they utter shrill cries, 



I \ "^, 



Fig 178.— The Australian Ckane {l 



Aicsimlu). 



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 at- 

 tained sufficient height to pass over the obstacle, when, assuming their original 

 formation, they proceed 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 more power- 

 ful by the peculiar conformation of the windpipe, which forms several curva- 

 tures in the breast-bone before descending into and joining the lungs. The 

 crane is a tall and stately bird ; when it stands upright it reaches to the breast 

 of a man, and the wings, when extended, are about seven feet in breadth. It 

 is of a shy and wary disposition ; and when a large flock alight in a field, 

 either for the purpose of feeding or resting, one or more of the party is always 

 seen standing at some little distance, with head erect, and evidently on the 

 watch. On the approach of danger, this individual is the first to give the 



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