OF NATURAL HISTORY. 491 



ty in their movements. They fometimes form a flraight 

 line ; and, at others, they afTume the fhape of a wedge, 

 which facilitates their progrefs through the refilling air. 



With regard to the wild-duck, pochard, wigeon, and tea), 

 though Mr. White places them in the Hft of birds of paflage, 

 he does not mention either the times of their arrival or de- 

 parture. Though it be probable that mod of the duck-kind 

 migrate, yet it is certain, that fome individuals of different 

 fpecies of them breed in this country, and continue in it dur- 

 ing the whole year. As to the duck-kind in general, Mr. 

 Pennant remarks : < Of the numerous fpecies that form this 



< genus, we know of no more than five that breed here. The 



* tamefiuan and tame goofe^ the Shield duck^ the eider ducky and 



< a very fmall portion of the wild ducks. The reft contribute 

 ' to form that amazing multitude of water fowl that annually 

 « repair from moft parts of Europe to the woods and 

 « lakes of Lapland, and other Arctic regions*, there to per- 



* form the funiftions of incubation and nutrition in full fecu- 



* rity. They and their young quit their retreat in Septem- 



< ber, and difperfe themfelves over Europe. With us they 



< make their appearance the beginning of Odlober, circulate 



< firft round our fliores, and when compelled by fevere froft, 



< betake themfelves to our lakes and riversy.' 



In winter, the bernacles, or brent-ducks, appear in vaft 

 flocks on the north-wefi: coafts of Britain. They are very 

 fliy and wild ; but, when taken, they foon grow as familiar 

 as our domeftic ducks. They leave the Britifh fliores in Fe- 

 bruary, and migrate as far as Lapland, Greenland, and even 

 SpitfbergenJ. 



The folan-gcefe, or gannats, are Hkewlfe birds of pafTage. 

 They frequent the ifle of Ailfay, near the Frith of Clyde ; 



• Collea. Voyag. Dutcli EaR India Company, 8vo. 1703. page ig. Cluii 

 Exot. page 368. 



f Pennant's Britifh Zoology, vol. a. page 5 19 y.o. 

 \ Linn, Amoen Acad. torn. 4. page 585. Barent's Voyage, p-.ge 19. 



