Marshall (1942) Chamaethlypis poliocephala Lake Olomega # 1913 coll as sang from top clump of grass & from a vine-entangled sm. tree at edge grassland. Pleasing song. V de Santa Ana # 2304 & 2305 coll together as they foraged in chaparral grown into old clearing on E base Ceno de los Naranjos. They looked & acted just like Tolmie W. to my opinion, tail much longer & held up at angle, however. This was edge of chaparral area - this brush followed course of little creeks and gulleys across cleared cornfields & along these straggling lines of brush. this sp. was abundant and everywhere heard or seen. Paired. Other gulleys mentioned under Catharus, Geothlypis, & E. alligatoris were thin coffee shrub plantings of Castor trees. The present sp. not there - only next to corn fields, often singing abundantly in cypress hedges next to fields - hard out in fields but always fly to edge when approach. Call note very slightly but haunting & very distinctive reminds of calls of other open-field birds. Sparrow sparrow, lared larks, etc. Heard from fields on 1.