10 \\"arbij<;r soNCrS. 



of a single note like the Chipping Sparrow, the other a com- 

 posite song so varied that it approaches a mimicry of many 

 songs. I have selected the Yellow Warbler as representing 

 nearly the type song of the family. We might further say 

 that this type song usually consists of about eight syllables, 

 the first phrase of four or five uttered more slowly, the remain- 

 der more rapidly and on a different pitch, sometimes higher, 

 sometimes lower. With some species the pitch is so high that 

 it approaches the vanishing point to many ears. But there 

 is an indefinable woodsy quality to all warbler songs which is 

 not shared by the members of any other group which bears 

 any troublesome resemblence to the warbler songs. It is a 

 quality that can be learned in a little time with the birds as 

 they sing, but cannot be transferred by word of mouth or 

 printed signs. Before leaving the song-type let me define the 

 hissing whistle. It can be closely imitated by forcing the 

 breath over the tip of the tongue as it is held against the 

 upper teeth, modulating the pitch of the resulting thin whistle 

 with the lips instead of with the tongue as in the ordinary 

 direct whistle. 



SONG PERIODS. DIURNAL. 



Having learned the Warbler song-type, we are prepared to 

 begin a study of the separate songs as the species pass in 

 review before us. We shall not proceed far in this study before 

 we discover that certain times of the day are preferred for 

 singing by most of the species. Their day begins in the early 

 morning twilight with a burst of .-song, and is carried with the 

 quest for food as the light strengthens ; the intervals between 

 songs gradually lengthening as the da}' advances, until the 

 appetite is satisfied, when the bird ceases song to rest until the 

 afternoon brings round the feeding time again. The after- 

 noon song period is marked by less singing than the morning, 

 and the twilight marks its close. It is difficult to say when 

 the morning period ends and the afternoon begins in the case 

 of any individual birds ; but in general, we hear few songs 

 between ten in the morning and three in the afternoon, es- 

 pecially during warm weather, when the noon hours are of 

 high temperature. During cool or wet weather the morning 

 period begins later and the evening closes earlier, while some 



