C. humilis 91 Rio Ostuto, 6mi. W Zaratanes May 2 we do it is commonest variation of song, almost every song is similar to we do it - without the second syllable. Have a series shit or shoy - neal notes. Also hide a lot collected the pair observed (#1) - F shows beginning of a brood patch. This pair ranged into a fair sized guanacaste near the nest. Just after collecting the two birds (#1) which were together and obviously paired - I heard another sing in the same tree - a guanache - about 25 feet up. It answered my imitations of its call. Collected it (#2), May have been a bird from an adjacent pair or group?, in any case I had not seen it before while watching the pair. Nest in BHA 20 feet up. Single nest. Pair present. I shot O which was singing. I went to nest - I tapped nest and she flew out, perched, and gave a trill, quite long. Later, I found humilis fairly common in a dry low stand of acacia (BHA & others) and a guanache like short tree. This stand was along the river or a dry draw but well short from the water. This vegetation is same as that near Arriaga where we hunted along the last river near town - also similar to Acapulco vegetation where this wren occurs.