Oct. 28 Pitahaya, 40 km. SE Empalme, 100 feet, Sonora. Last night we had an intermittent but strong rain. The day has been warm and muggy. Hunted south of camp through scrub and along thickets bordering the "laguna," which might best be called a temporary slough. Camp is located on a point extending out into it along its south, east border. The slough itself, cut about midway by the railroad, is approximately 1 1/2 miles long and 1/4 to 1/2 mile wide. There is extensive growth of a leguminous shrubby plant which Leopold calls Cassia. The slough is bordered by flats, muddied by recent rains, and the area of the slough probably is just one extensive dry mud flat in the spring and early summer. There is enough water now so that the laguna is attractive to waterfowl, and we have seen several large flocks of pintails, shovellers, and probably other species. There is also a variety of shorebirds. The land birds seem to be preponderantly migrants -- sparrows, warblers, Orioles, green-tailed towhees, house wrens, etc. Species which are common and probably resident are mockingbird, verdin, gila and ladder-backed woodpeckers, gilded flickers, rufous-winged sparrows, and Gambel Quail. Also cardinals and Pyrrhuloxias.