248 FACULTIES OF BIRDS. 



CHAPTER XII. 



MIGRATION OF BIRDS. 



FEW subjects connected with natural history are 

 more interesting, or have more attracted the attention 

 of ordinary observers, than the periodical appearance 

 and disappearance of certain species of birds. These 

 curious phenomena have been noticed in all ages and 

 countries ; the sages of old, as well as the scientific 

 of our own days, have looked upon them with in- 

 terest; and to the agriculturist, the shepherd, and all 

 whose occupations lead them to the fields, the woods, 

 or the hills, they are in some measure familiar. Even 

 the inspired seer has found in them an illustration 

 suited to his purpose : a The stork in the heaven," 

 says the prophet Jeremiah, " knoweth her appointed 

 times; and the turtle, and thecraiie, and the swallow 

 observe the time of their coming. 1 ' 



In our latitudes the migration of birds is two-fold ; 

 in other words, there is a passage northwards and a 

 passage southwards. Or, we may divide the birds 

 that occur in any of the temperate climates of the 

 northern hemisphere into permanent residents ; birds 

 that breed and remain all summer to retire south- 

 wards in autumn ; birds that visit us in winter and 

 return in spring to breed in more northern regions ; 

 and, lastly, birds that sojourn with us only for a short 

 period on their passage northward in spring, and 

 again on their return in autumn. 



Among the permanent residents, there are species 

 which perform a limited migration, shifting from 

 one part of the country to another, according to local 



