the tree tops and moving swiftly southward. During some nightS 
they seemed to be passing in endless procession yet rarely in close 
companionship. 
This I inferred from the fact that it was exceptional to 
hear more than one of them in any given direction at any one time 
and equally so for many minutes to elapse when none were noted. 
Not infrequently the last faint call of one that was just passing 
out of earshot to the southward would be almost immediately fol¬ 
lowed by the first audible cry of another approaching from the 
northward. Plying thus singly, at widely spaced intervals, yet per¬ 
haps within distant hearing of one another, mingling their crisp, 
•» 
incisive voices with the feeble lisping ones of innumerable migrat¬ 
ing Warblers, the mysterious birds would journey almost ceaselessly 
southward along aerial pathways lighted only by the moon or by myri¬ 
ads of twinkling stars. Their calls which were seldom given often- 
er than once every eight or ten seconds and sometimes much less 
frequently, reminded me by turns of those of certain of our waders, 
of the autumnal note of the Rose-breasted Grosbeak and of the loud, 
explosive cry oi the Crested Flycatcher. On the whole, however, 
they resembled most closely the night calls of the Hermit Thrush. 
Indeed I was inclined for a time to refer them to that species un¬ 
til I learned that the birds making them habitually departed for 
the South before many, if any, of the Hermits had left their breed¬ 
ing grounds. This consideration ruled out Swainson's Thrush, also. 
