O. rufinucha x zonotus 12 mi. SSW Boca del Rio, 100ft., Veracruz May 18-20 Pair 2285-2286 - I had egg yolk in oviduct yet -> tetr a rather small - these saved for examination. On May 18 & 19 I watched a pair sing together, -> giving a two note call - wa-chet, etc. - very sharp staccato while I gave a soft chu-do-it . This is common thing - and I given by pairs of humilis also . Two different calls given at same time . Perhaps, then, the communal call of the O? is the two-note one , but I have seen O?O? giving the triplet note also. When disturbed I watched a & give a continuous song, rather high pitched saw, saw, saw. I have seen several nests here. Both were placed in the ocacia which resembles the 13 HA of Tonal's but which has the spinea winding about the stem. Usually nests are placed below 8 feet - most about 4-5 feet above the ground. All were small - about same size as humilis although rufinucha is a larger bird. The construction is simple a little of dry grass & fine stones lined inside with matted vegetation fiber. There is a short tunnel at the opening but this is not conspicuous and the nests appear to be almost perfectly oval. The nest of the social flycatcher is similar in size (a bit larger usually) and placement but the latter in construction and invariably has a bunch of long straws hanging under the entrance. I have seen no evidence that rufinucha builds more than a single nest and all birds encountered were in