22 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I43 



which a tanager or a honeycreeper was the active agent — in this case 

 the attacker — and the specific identities of both the supplanting and 

 supplanted birds were clear. 



Table 7 is a very partial indication of the frequency with which some 

 species failed to induce interspecific reactions when such reactions 

 might have been expected. It is a list of the number of times species 

 of finches, tanagers, and honeycreepers were seen to fly away from 

 mixed flocks in a very conspicuous manner (giving loud flight calls 

 or call notes and performing exaggerated intention movements of 

 flight before leaving) without being followed by any other species of 

 the flocks. These incidents were also observed between October 26 

 and December 20. 



Table 7. — Data from observations in and around the clearing on Barro Colorado 

 Island between October 26 and December 20, 1939 



The number of times species of the blue and green tanager and honeycreeper 



alliance were seen to leave mixed flocks in a very conspicuous manner without 



being followed by individuals of other species. 



. No. of times 



Species seen 



Plain-colored tanager 40 



Palm tanager 9 



Blue tanager 13 



Red-legged blue honeycreeper 3 



Bananaquit 1 



Tables 8 to 19 are designed to show the frequencies with which 

 the 12 most commonly observed species of tanagers, honeycreepers, 

 and warblers (the same species shown in tables 1 and 2) were asso- 

 ciated with one another in mixed flocks on Barro Colorado Island 

 during the whole period between October 26 and December 20. Each 

 species is treated in a separate table, showing the number of times it 

 was seen with every other species in flocks composed of two species 

 and in flocks composed of three or more species. Every association 

 between two species, even in flocks of three or more species, is counted 

 separately. Thus, for instance, if plain-colored tanagers, palm tana- 

 gers, and blue tanagers were seen together in the same flock, their 

 group was recorded as one association between plain-colored tanagers 

 and palm tanagers, one association between plain-colored tanagers and 

 blue tanagers, and one association between palm tanagers and blue 

 tanagers. The figures in these tables are counts of associations between 

 species, not individuals. When several individuals of each of two 

 species were seen together in the same flock, their group was counted 

 as a single association between the two species. 



