INTRODUCTORY. 



Longfellow says : 



Birds of passage sailed through the leaden air from the ice- 

 bound, 

 Desolate northern bays to the shores of the tropical islands." 



Tennyson calls them, 



" Wild birds that change 

 Their season in the night, and wail their way 

 From cloud to cloud." 



Our birds move southward on the approach 

 of autumn. Some, like the swallows and the male 

 warblers, retreat when summer has just passed its 

 climax ; others tarry till the snows and frosts of 

 winter compel their departure. Some, like the 

 robin and sparrows, merely go to the Northern 

 or Middle States ; while others, as the swallows, 

 the redstart, and some other warblers, find a winter 

 home on the sunny shores of the Mexican Gulf, 

 or even in South America. Their line of migra- 

 tion is down the Atlantic coast. They cross the 

 Gulf of Mexico by passing from Florida to Cuba, 

 and thence to Yucatan. 



Some of our birds, as the sparrows, thrushes, 

 and warblers, move leisurely in their migrations, 

 feeding their way from post to post, and occupy 



