37 



the British Channel, saw a vast number of 

 swallows resting on the standing rushes, who 

 so soon as the sun got up, and the mistiness 

 of the morning broke off, took wing, and flew over 

 sea, and were no more seen. He mentions also, 

 that his brother in Andalusia constantly observ- 

 ed the migration of swallows and other birds, 

 annually traversing the Straits from North to 

 South in autumn, and back again in spring. 



Lieut. Col. Macironi assures me that he has 

 seen large flights of swallows crossing the Me- 

 diterranean when out at sea, and has likewise seen 

 them fly in large bodies out to sea, from the shores 

 of Italy, in autumn, in a southern direction. 



If swallows uniformly appear in Senegal when 

 they disappear in almost every country of Eu- 

 rope, and at no other time ; and if they regu- 

 larly appear in most parts of Europe when they 

 disappear in Senegal, and at no other time, 

 (which, according to Adanson, is the case,) it 

 seems reasonable to conclude, that Senegal and 

 other warm regions of Africa, and the cold 

 and temperate countries of Europe and Asia, 

 are alternately inhabited by the same birds. 



