5 mi. N Tehuacan', 1676 m. May 27 the nest in the large mesquite tree yesterday but I cannot be absolutely certain of this. In the mid-morning I flushed a ♀ (see [illegible]) from a nest in a small 'olivo-type' tree down near the mossy area. She had a good brood-patch but there were no eggs in the nest. I heard another one calling in a nearby tree but could not locate it. Calls: ① gu-gu-gu-gua-gua-gua - very fast and very similar to 'guo' call of brunneica pillosa from which it differs only in being a bit higher pitched, and of weaker volume. Often this call changes to a che-che-che-che which is higher pitched. When I flushed a ♀ from a nest (containing eggs) she flew to a nearby tree and gave the gu-gu-gua call - so apparently both sexes give this. ② the che-che-che-che-shit call is different from ① but the two are similar in tempo and the ① may be followed by ② without a break. This call is tense and, increased slightly in pitch as given, is higher pitched and When two birds meet this is the call given - usually by both birds excitedly - not often together in perfect unison, however. It exceeds the calls of himalana or rufinucha under similar circumstances. ?? ③ che-che-who - I heard one bird give this twice very softly - twice - but I cannot even be certain it was a corten wren although the tone quality was wren-like.