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Atlapetes, May 24, 1961, II.   54

have been the occasional addition of a third, whistle-like, "Wheeoo" note, right after the first two, and/or the occasional omission of one of the terminal "Tsit" notes.
  
I only observed the birds on Atacaso this morning. Just at dawn, at least three birds began to utter typical "Wheeoo, wheeoo, tsit-tsit-tsit" songs. Again no rattle. Then, a few minutes after dawn, some or all of them began to add rattles to their songs. Comme ça "Wheeoo, wheeoo chip chip chip [[image - jagged line]]."
  
This difference between the songs of the Inaquito bird and those of the Atacaso birds is the same as last year. Last year, I suggested that the incorporation of hostile R's into the songs of the Atacaso birds was an indication that they were comparatively retarded in the breeding cycle. This may well be true. If so, the sex or pairing drives of the Atacaso birds this morning must have been relatively stronger (in comparison with their hostile drives) just at dawn than a few seconds later. (This is probably not surprising. I think the birds start to move around a bit just after dawn. They may then become more conscious of other [[male symbol]]'s in the neighborhood.)
  
I have several times heard [[male symbol]] rufuincha singing as they moved along hedges or through thickets. This tendency to sing while moving may be a significant resemblance to gutturales. 
  
The only bird I have been able to see very well while singing is the Inaquito bird. Slight CR. Bill opening and closing with each note of the songs. No trace of wing movements like those of gutturales.
  
I have been paying special attention to the call notes and similar notes uttered by the birds apart from song.
  
Both single birds and pairs sometimes utter single "Tsit" notes when they are hopping in thickets and/or flying. There notes are