S. P. Nyeus 1974 Tryngite subtruficollis 35 (0.18) region Estancia Medaland, 35 km S. of Tumeler by road, Pto de Madariaga, Pcia de Bs. Aires, Argentina. 17 September (cont'd) others are foraging in 'circle', no parallel orientation. Aggression. one (buffy 9-17-74 A) has its head up, chasing other birds out of slight depression a meter or two in width, chasing again, still with head up. (9-17-74 A is in flock B), which went ~70m beyond B) 0740 chased others out of depression, but another buffy is preening at the lip of the depression. Rest of 4 moved away. 9-17-74A appears to be tolerating another buffy within 1km confines of its foraging area - it has gone 10-15 m to the NW from depression 0743 B in still there, 18 total of which 7 are preening. considerable aggression. 0945 resting+preening, beside of Bare facing up, SSE wind, some punched behind grass (it but most not). 0746 flock A obviously static - much aggression, some of it appears to be space specific. Tail down!, but most of it in 'circle' supplementation with topography no more than lowered head - charge + raised head running. Another Whin-cup, with same terminal as described last page. @@@@ (buffy was lone by 9-17-74A. it was then chased by a Phylidris 0747 A is perched behind) small clump of grass, preening. Dispersed other birds. [it is very difficult from this (Down angle to look at spatial relationships between (buffy] 0751 a (buffy entering area where 9-17-74A was chasing others from. within 3 sec of my noticing the ??? intruding, 9-17-74A stopped preening + chased the intruder off. i.e. thus is some space-specificity 0753 9-17-74A approaching behind another clump of grass less than 1m from original after having chased them with several m away. Many of the other local buffies are also preening now - dispersed - 10m, 3m, etc from one another. There are a few staying close 0754 flock B is still (where it was). 0755 9-17-74A left preening + began feeding. Every one in a while does its tail go down - no one in immediate vicinity, no one approaching, but the black strip down the tail is obvious [it was very interesting to watch the circled flock (A+B) lose members and finally come to a halt, and its members show some degree of space-specific behavior] 9-17-74A climbing up a 25cm ant nest - perching behind it, less than 2m from another buffy resting. Now other buffy walking towards A, within 30cm. A' (raiding) head, ran after it. Then scratched and returned to perch. Other buffy went to original position + is preening. This was not