LLW01f 1964 Oriturus superciliosus August 11 La Ni. N. Tres Cumbres, 7100 ft., Morelos, Mexico grass when woods grass just larger the ground. several times heard chatters seemed to be always given by same bird. much chatterd as flew down little incline 3-4 feet to join other kid. watched several erratic dashes while foraging as if chasing an enemy. foraged in closed ellipse & then repeated the tour coming much the same route. two birds generally stayed together, but occasionally became separated by 10+ yds. two other adults--one 3rd bird that flew uphill--utilized area just S of pin. one foraged in pretty same area as first pair when two areas meet. foraged in open, 1 inch grass then flew up into same pin used by pair 1. moved to top & began counter-chatter with bird in next pin to S. two then came together & flew off to S. Song sometimes elaborates into dry chatters with spirid fill at end. adult Flushed F from nest in clump of bunch grass. Nest on west side of clump+ on top of tussock. Adult fluttered out + disappeared to N. Did not return when checked nest area 2 more times in one hour. Made of grass + contained 3 whitish eggs with reddish-brown spots--heaviest at large end.