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 Jan., 1914 11 NOTES ON THE DERBY FLYCATCHER By ADRIAAN VAN ROSSEM D JRING the six months between February 0 and August , ][912, while collecting in the little republic of Salvador on the west coast of Central America, it was my fortune to make a more than casual acquaintance with the Derby Flycatcher (Pitangus sulph,.tratus derbianus). Though extensive notes vCere taken on the birds themselves there are many points in regard to incuba- tion, care of the young, etc., which, in the pursuit of other equally interesting species an(t frequent change of collecting ground, were passed over. Aside from the superabundant and ever-present Black Vultu,'e (Catharista atrata) or "Sope" (which name, by the way, is occasionally given to the priests because of the merely external resemblance), no bird is better known by the na- tive population, or more quickly noticed by even the most disinterested visitor than the strikingly colored and noisy "Chio", not so much because of the abun- dance of the latter birds, but because with the exception of a few Nicaraguan Boat-tailed Grackles (Megaquiscalus nicaraguensis subsp.?) or stray Giraud Flycatchers (Myioxetetes texensis texensis) they are practically the only small bird to be found inside the larger towns. Though noted in greater or lesser num- bers in every locality visited, from the top of Volcan de San Salvador to the man- grove swamps along the coast, the center of their abundance is the highly culti- vated district surrounding the two largest cities, San Salvador and Santa Ana, which are situated at about two thousand feet above sea level. Toward the two extremes of altitude (sea level and 70oo feet) the birds become scarcer; decidedly so in the mountains and to a much less degree at the coast. At Acajutla, the port of entry, they were quite common. The intermediate zone is, as has been men- tioned above, under intense cultivation, but at the same time is criss-crossed and cut by innumerable steep-banked gullies varying in depth from a few feet to over a hundred, most of the larger ones containing water, and all, of course, hung with a tangle of tropical growth. Some of the narrower of these gullies are complete- ly arched by tree s growing on the rims. These ravines together with the tiny "fincas" or farms placed on the ridges (sometimes half a mile wide) between, make from a Derby standpoint an ideal breeding locality, as proven by the pres- ence of numerous nesting pairs. At a lower elevation where the more open coun- try is. given over to cattle pastures they are also very common but d not seem to nest, as a general thing, so close to the ranch houses as in densely populated sec- tions. These birds were found in considerable numbers, too, around Lakes Ilo- pango and Chanmico. At the time of my arrival Derby Flycatchers were already paired off, but it was not until the first week in March that nest-building in the vicinity of San Salvador at least had commenced. The first nest which came under observation was about half completed on the I5th and xvas collected with four fresh eggs on the 28th. In this instance, then, nearly a month must have been required to build the nest and lay the full complement of eggs. .Perhaps this time is unusually long, but as all that were subsequently found were already occupied at the time of discovery there was no means of determining this point. A wide variety of nesting sites is chosen. Near San Salvador where cocoanut palms are abundant these are generally selected, the nest resting on one or two Of' the lower fronds at their juncture with the main stem. Ordinarily a rather short palm is used, an average height being', say, twenty feet..The lowest was a scant six; the highest a 'good fifty. In the lower country a small mesquite-