The Birds and Poets 165 



Among the common birds that leave us in Sep- 

 tember are the swallows. They are usually all gone 

 by the middle of the month, and have never been 

 known to vary more than a few days in the date of 

 their annual departure. Swallows feed upon 

 insects captured while flying, so there is really no 

 apparent reason for their migrating so early, as 

 there are plenty of insects to be found long after 

 they have left us. 



The chimney swift, one of the most interesting 

 subjects for the student of birds, is popularly con- 

 fused with the swallows, and is often mis-called 

 chimney swallow, but the resemblance is only 

 superficial, while the structural differences 

 between the two are numerous and important. 

 Structurally the swift is related to the humming 

 birds and not to the swallows. It feeds entirely on 

 the wing, and has never been seen perching any- 

 where except on the inside of a chimney or hollow 

 tree. Except when nesting or roosting therefore, 

 it is constantly on the wing, even drinking, and 

 gathering dead twigs for its nest while flying. 

 They skim over the surface of the water and dip 

 their bills into it while on the wing. Tennyson 

 speaks of the "skimming swallows," and Virgil 

 wrote : 



"The twittering swallow skims the dimpled lake."* 



They have been observed dashing swiftly past 

 old dead trees, catching at the ends of dead twigs, 



* "Aut arguta lacus circumvolitavit hirundo." 



