LLWOIT 1964 Aimophila humeralis July 14 Canyon de Lobos, Gto., E. Culiacan, Mexico 0800 - found two birds on Acacia-dominated hillside. Most of trees < 15', but these birds were in 20' tree - with several other trees of about same size formed nearly closed canopy in area otherwise very open. Seemed to be foraging up to 10' above ground or set on dead perch. Call tzzeet, tzzeet, a soft trill, a single note. 0808 - one bird flew up to tip of branch among leaves + pecked + pulled in foliage. Changed positions slightly + continued to pull + pull at foliage. Came up with a larva - flew down to bare branch where it ate - did not seem to perch on limb - but probably only flew down to advance shedding perch, then back up to canopy. 0810 - other bird hopping along bare vine in subcanopy. Pecked at insect on branch + watched it fall to ground. Then sat preening + calling - tzzeet + rapid, soft dry, trills. 0840 - back to this pair after searching for others. Flew along hillside + one lit in Acacia just in front of me. Other more hidden. Gave soft trill + short portion of chatter. Then flew 20' further + began chatter. Noticed dog coming up path. It's dog turned back. Both birds flew over to follow for 10-15' + one was chattering. Other flew up with larva in bill, lit on bare limb + manipulated larva for few times then flicked it against limb - raised then till once + swallowed it end first. I walked in to where birds were - one went to E + other to N ~ 20'. Began soft trill + short chatter. Seemed to answer with chattering other chattered. Finally came together + both