JPMycs 1974 Tryngites subbifocillus Tower Llanos, Estancia Medland, 35 Km S. of Juancho by road, Pto de Madaringa, Proia de Buenos Aires, Argentina 23 January (cont'd) Lois recorded following data on Buffy 1/23 C from 1000 to 1100, during which time the 1/23 C remained on or near the grid. This bird concentrated its activity within (3,4), (3,3) and (4,4), with some activity to the W of the grid. All but 13 of the 60 sample points were within the 3 units. Defended area calculated as 40 ~ 100 m². 1/23 C shared a boundary with K. In the hour, 1/23 C attacked appeared 7 times, without being chased by another buffy, although it was chased by Golden Ternice. At 1123 L finished a second set of following data on 1/23 K - probably K. 1/23 K remained on grid for the entire sample period. Activity center concentrated in (3,4) (1,4) (4,0) (order of maximum (ordered by % of sampled units, starting with max) (2,4) = 14 minutes; (1,4) = 7 min; (3,3) 7 min, (3,1) 6 min.... Area defended ~ 250 m. Border shared with 1/23 C - in same site as that defended by K - I am positin that there are K and 1/23 K' on the same grid. Therefore this buffy has defended the same territory 0751-1123, or almost 4 hours. It is unlikely to be the same bird that the lower border of K has retracted somewhat: in the 0751-0851 reading, K defended the 0, n -1, N areas entirely. However 1/23 K' has a border with another buffy in the (n,1) units. I.e. (0,0), (0,1), (1,0) and (1,1) are now in the control of another bird (which Lois followed from 1100 to 1200 [1/23 D.], 1/23 D. foraged principally in (n,1) and a bird almost certainly identical to L (above). However, 1/23 D did not remain for the entire 60 min. sample period, leaving after 51 minutes. Foraging concentrated in (n,0) and (n,1) units, especially the latter. Border as noted above with 1/23 K'. During 51 min, chased others once, by others 4 times. During the final minute of following data on 1/23 K', an extensive interaction between it and 1/23 D began. 1/23 K' chased D out of (1,3), flying a distance of 11 m. D flew to the lower part of (2,1). (2,1), ~ 5 m, and both birds watched, ~ 5 m apart, and have remained preciously