LHWoff 1964 Aimophila humeralis July 23 (area de lobos, Quid E. Cuernavaca, Morelos, Mexico) + flicking right wing. Then hear [call note] from near top of tree #1 + two birds fly up there (chattering pair) + chatter - can only see one bird. This one wing flicking vigorously - most right, but occasionally the left + for several seconds had both going slightly. Then two birds flew off to NW into dense shrubs + chatter followed by chatter from area #2. Then third bird flew down to where two (area #1) had earlier gone. 0734- simple pizza followed by chatter in area #1. 0742 - sharp chips from area #2 - followed by chatter from area #1. 0750 - pizza notes from near boundary of area #2 & #3. Followed + coincident with pizza notes from area #2. Then chatter from tree #1, bird then flies to N to tree #3 + another up into shrub 10-15 yds. to E. Solo chatter + splutter followed by pizza notes from #3 + chatter from #1: then #3 pair to tree #2 where chatter + pair #2 also chatters. One of pair to them to S. Other up into tree. 0755 - one of pair #3 from tree #2 uphill to W when hear pizza + then chatter. 0757 - several chatters from area #3 & [one] from area #2 both were uphill from trees #2 & #3. 0806 - watched bird in partly defoliated tree. Walked near tips of branches + from just below canopy, caught a Lepid. larva. Then flew over to wooded gully. 0809- heard pizza notes + bird flew up into upper branches of tree #2 when joined by another bird + chatter.