R.K. Selander, 1954 C. nigricaudatus 38 Rancho Orezon, SE Tonalá, Chio., Mexico March 31 our present position. the road is terrible, however, and we have had much trouble with large boulders in the middle of the road so I doubt that we will be able to continue further down towards Tres Picos. I thought that we were on the SE end of the Ocuilapa Valley but I think that it continues further SE. In any event it appears to narrow here at camp as a dome-like hill on which we are camped splits the valley into two smaller ones. This formation may act as a barrier to nigricaudatus provided that form does not inhabit this foot-hill type deciduous or sub-deciduous forest. Perhaps clearing of patches of forest has allowed humilis and nigricaudatus to come into contact. This can be shown if we find these birds only at edge of cleared areas as we have in the past. April 1 Hunted wrens NE of camp in early morning and collected 8; of which at least 7 are good nigricaudatus; one other has a more patterned look than in pure nigricaudatus. We found these wrens in dense clumps of thorn bushes along the fence and in the small gullies. One group of 3 wrens we found in a short palm tree in the yard of a ranch. These flew to a large guanacaste tree when we shot at them in the palm. There we severed their, short buds from acacia trees near the palm. The wrens seemed more wary than those near Ocuilapa and kept well down in the dense bushy vegetation - most of which