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Mixed Diglossini, Apr. 11, 1963, VI 
[[circled]] 7 [[/circled]]

[[margin]] Poospiziopsis [[/margin]]  The presence of this species in this area has interesting implications.  It may help to explain why both CC's and Bruns are so surprisingly rare here.  Looking at the GC's, I find it difficult to believe that they can be strong competitors of Bruns (at least); but I can think of no other aspect of the environment that could account for the rarity or absence of Bruns in parts of this area which appear to be otherwise very suitable.

[[margin]] CC Brun [[/margin]] The behavior of the CC's observed this morning was much the same as that of the CC's observed near Tarma.  This, and the fact that the "Orange-bills" were so vocal this morning, would suggest that all or most of the birds here are at the same stage of the breeding cycle or the Tarma birds a couple of days ago.  The Bruns were probably comparatively quiet because they are so rare here — there are so few of them to stimulate and/or initate one another.

[[margin]] Poos. [[/margin]] In any care, the GC's were certainly singing very frequently.  Suggesting that they were highly motivated. 

[[margin]] CC Brun [[/margin]] As far as I could tell, the territories of the GC's did not overlap those of either CC's or Bruns — or at least overlapped only slightly at the borders.  And even though at least one CC and one Brun were seen in almost the same bushes (at different times), it is quite possible that their territories were also eventually non-overlapping.

[[margin]] Poss CC [[/margin]] I did not hear any overlaps between songs of different species of diglossini.  The CC's and Bruns were too rare to expect their songs to overlap with one another or with those of other species.

[[margin]] Brun [[/margin]] Nor did I hear any intra-specific overlapping of songs. Again the CC's and Bruns were too rare for this to be expected.  But it may be significant that the GC's did not overlap with one another.