K. Selander, 1954 17 C. chiapensis (as humilis). SE of Tonalá, Chis., México March 24 Drove out on road to Ocuilapa as far as Rancho Ocuilapa. At a point 2.6 mi. SE of the Rio Sanatanco near Tonalá we found a group of chiapensis in a fairly typical situation, although the country along this road is much drier - large grassy fields - and few mangos and other large trees, although the guaracaste is common & sometimes huge. Near the road where we stopped I heard a wren singing clearly 20-15 feet up in a dry open tree - "look- at-me-caw", "look-at-me-caw", "look-at- me-caw." I recognized it as a wren ca song. Shot the bird - a male, which may be intergradent with nigricaudatus. No other small cactus wrens were seen but we noted a nest in a bush-horn acacia about 30 yds from the tree. Will investigate the nest later. This is the same area in which I observed a pair of small cactus wrens in October - and in view of the larger size and white belly of the specimen taken today I am no longer sure that the two birds seen in October were nigricaudatus as I thought at that time. We drove on toward Ocuilapa after making one short stop between 2.6 mi. SE & Ocuilapa where we hunted without finding and cactus wrens. Made general observations of Thyrothorus pleuraticus along the way and took a specimen 4.8 mi. SE Tonalá. At Rancho Ocuilapa, which is located