The Bachman's Sparrow (Aimophila aestivalis bachmani) is known to be quite rare and irregular in distribution in the northern part of its range. Because of this the northern limits of its range have been rather ill-defined. According to the A. 0. U. Check-List, Fourth Edition: 343, 1931, this bird ranges north to central Virginia in the eastern part of its range and is casual near Washington, D. C. Its distribution in the north-central portion of its range, including the Appalachian Mountains, is discussed in detail by Brooks (Wilson Bull., 50: 86-109, 1938). The discovery in May, 1942, of three pairs of these birds nesting on the Beltsville Research Center, Prince George County, Maryland, considerably extends the northern limits of the known breeding range of this species in the Piedmont and coastal-plain region east of the Appalachian Mountains.