LLWOLF 1963 Aimophila mystacalis August 11 11 miles SW. Matatlan, Oaxaca, Mexico km. 608. habitat singing ♂♂ spaced out over thorn scrub & up into scrub oak on hillside above Pan American highway. Found one pair. John collected a juvenile which was almost thru the post-jaw molt. Adult ♀♀ collected showed evidence - blood patch ovary - of nesting about to begin. Apparently two broods. Heard several reunion chatters that sounded as if both birds were participating. Not able to see birds so they chatter so still not sure that ♀ contributor. chut August 12 km. 616 on Pan Am. Hwy S. of Oaxaca, Oaxaca ♂ in top of 15-20 foot tree. First located while singing. prefect/fairfield/ then began to preen. While preening gave occasional 13cet note accompanied by flick of tail. then back to singing ? ---- or ? ? or ?. Next (0730) found pair together near top of 15' foot tree. ♂ flew slightly uphill for about 20 yards & lit just above ground. 2nd followed. One began calling at dead wood stems then both disappeared along slope. ♂ then up to 15-20 foot perch on dead limb ~ 3 feet from top of tree. Sat about 12" from trunk & singing - ♀ flew off perch & dropped down to near ground then flew along slope for 20-30 yards. Could see a chase with ♂ chasing a 2nd bird - probably the ♀. Both went uphill for 10+ yards & worked to ground or near ground in relatively dense herb & shrub layer vegetation, saw her ♂x♀