November 1950 Crotophaga ani Nov. 1 5km N Villavicija, 1400 ft., Huila, Colombia, S.A. presumably from the same flock - both were females. We are beginning to wonder if the sexes are flocking together at this season. Local name is "hiriquelo" ("irihuelo?") Nov. 2 A flock of about 5 seen about 500 yds. N of Duebrada Tajae bridge. I assume all were C. ani, accompanied by about 4-5 C. sulcirostris. Calls of both species were heard and I tried as best I could to refer the calls to individual birds. My identification by call seemed to be confirmed by size differences. (the size difference which seems so time apparent is mostly a difference in tail sizes length, I believe. Nov. 3 One of three four birds shot from a flock near the mouth of Duebrada Cerbatava was of this species; the other three were C. sulcirostris. Nov. 5 Flock containing at least three C. ani about 1 km. N Villavicija near R.R. tracks. Nov. 8 Villavicija, 1400 ft., Huila, Colombia, S.A. Calls heard several times on island next to town. This species was the only Crotophaga species heard on the island.