CRANES. 



36' 



Europe in the montli of April or May, passing the fine weather in 

 more northern countries. Towards the middle of October, on the 

 arrival of the first cold weather, they leave us, in order to winter 

 in Egypt, Abyssinia, or even Southern Asia. They travel in 

 flocks, numbering sometimes 

 as many as three or four hun- 

 dred birds ; generally they 

 arrange themselves in two 

 lines, so as to form an isosceles 

 triangle, or a sort of wedge 

 with the point in front — the 

 most convenient formation 

 for cleaving the air with the 

 least amount of fatigue. From 

 time immemorial people have 

 been fond of saying that these 

 birds intrust the care of their 

 guidance to a chief, who, after 

 having led the way for a 

 certain time, and b3coming 

 wearied, surrenders his charge 

 to one of his companions and 

 passes to the rear of the 

 band, where, like a new Cincinnatus, he resumes the position of 

 a simple citizen. The fact is, that the leader of the two files 

 changes perhaps ten times in a minute, and the apex of the angle 

 is occupied in succession by every Crane in the flock within a very 

 short space of time. 



Cranes almost always travel at night, and alight down on the 

 ground during daytime to seek their sustenance. Sometimes, 

 however, they do not stop, and continue to push on through space, 

 giving utterance to startling cries, which probably are intended 

 as a rallying summons to those of the band which seem tempted 

 to linger on their journey. "When they perceive a bird of prey, 

 or have to contend against a tempest, they abandon their iisual 

 formation, and collect in a circular mass, so as better to resist the 

 enemy. 



Fig. 142. — Ash-coloured Crane {Grus cinerea, Temm.). 



