THE INVITATION 207 



pairs, and their black caps and striped coats show 

 conspicuously. When they return in September 

 they are in troops or loose flocks, are of a uniform 

 dull drab or brindlish color, and are very fat. They 

 scour the treetops for a few days, almost eluding 

 the eye by their quick movements, and are gone. 



According to my own observation, the number of 

 species of warblers which one living in the middle 

 districts sees, on their return in the fall, is very 

 small compared with the number he may observe 

 migrating north in the spring. 



The yellow-rumped warblers are the most notice- 

 able of all in the autumn. They come about the 

 streets and garden, and seem especially drawn to 

 dry, leafless trees. They dart spitefully about, 

 uttering a sharp chirp. In Washington I have seen 

 them in the outskirts all winter. 



Audubon figures and describes over forty differ- 

 ent warblers. More recent writers have divided 

 and subdivided the group very much, giving new 

 names to new classifications. But this part is of 

 interest and value only to the professional orni- 

 thologist. 



The finest songster among the Sylvia, according 

 to my notions, is the black-throated greenback. 

 Its song is sweet and clear, but brief. 



The rarest of the species are Swainson's warbler, 

 said to be disappearing ; the cerulean warbler, said 

 to be abundant about Niagara; and the mourning 

 ground warbler, which I have found breeding about 

 the head- waters of the Delaware, in New York. 



