called again but I could not see it. Several minutes 
elapsed and again the whistle sounded but the bird had 
moved further off. I heard it twice after this but I 
followed the sound in vain.4t^nce the bird gave four 
whistles ( heu- heu- heu-heu ) and once three, but 
usually there were but two. The note, although whistle¬ 
like in character and easily imitated by the human 
whistle, has a peculiarly'deep and also somewhat resonant 
quality which makes it decidedly impressive when heard 
under conditions such as those which I have just described 
It is very loud at times and really startling in its 
intensity. Once to-night the bird followed it (that is, 
the double whistle) by a low choking sound which I do not 
remember ever hearing a Saw-whet utter before. It was 
qiite evident that the bird heard on this occasion was 
moving rather restlessly from place to place. It called 
about once every two or three minutes and never more than 
once (I thought) in the same spot. When it moved its 
position, it ordinarily went only thirty or forty yards 
before alighting again. All this I could tell by the 
evidence of my ears alone^for I did not once see the bird. 
