Pipilo fuscus Zerezo, 3 mi. N of Pachuca, 9000 ft, Hidalgo, Mex. July 3, 1946. well-developed food-path. The ovary measured 7 mm. and some of the follicles were expanded, although the oviduct was not expanded. This ? was apparently just coming in to breeding condition. The second bird taken was an adult with testes measuring 4 mm. The left outer tail-feather was being replaced. These 2 specimens would indicate that the breeding season at this locality was just getting under way. The plumage of the 2 birds is not excessively worn. It is possible that the altitude in which these birds were found has a retarding effect on the breeding cycle as compared with populations farther down, e.g. birds in the Valley of Mexico proper. Although these birds undoubtedly invaded this area because of man's clearing and planting, and although altitude may not be of primary importance in habitat selection, it is possible that altitude may have a primary effect on the timing of the breeding cycle. These birds gave no notes of any kind before they were collected. The preference for rally, open terrain, sparsely vegetated, is quite unlike that of the birds noted in the Valley of Mexico, which were found mostly along roadsides at the edges of the maqany fields. It would certainly appear that these birds