Pipilo fuscus Real del Monte, 9050 ft. Hidalgo, Mex. June 30, 1946 Corn, has limited the ranges of P. maculatus and P. macromya, and extended the range of P. fuscus. Furthermore, it would seem that altitude is of secondary importance in the distribution of P. fuscus, and that habitat is the controlling factor. Preferred habitat seemed to be open country with scattered, low shrub-vegetation. Maguey seems to be an ideal type of cover for these birds. The country between Tachuca and Real del Monte has is grown to rather heavy, low scrub, but there are clearings all the way up. Another Brown Towhee was seen about 2 mi. W of Real del Monte, elev. 9000 ft., prevailing vegetation being small oaks + juniper with shrub understory. The only real barrier to this bird around the Valley of Mexico would be solid fir-oak forest. It is possible that such barriers in time would be destroyed through the agency of man. Zerezo, 3 mi. N of Pachuca, 9000 ft., Hidalgo, Mex. July 3, 1946 Reference for the locality of Zerezo is "Atlas Geografico y Estadistico de la Republica Mexicana", published in 1944 by Libros y Revistas, S.A., Mexico, D.F. The American Geographical Society map of this area shows this town as "Terez". At 7 p.m. I took the road leading