TALLEY MOUNTAIN. Talley Mountain, also known as Cow Mountain, is thirteen miles southeast of Panther Junction in the Big Bend National Park in southern Brewster County (at 29°08' N, 103°10' W). At an elevation of 3,765 feet above sea level, it rises some 1,165 feet above Glenn Spring, a mile north. Shallow, stony soils on Talley Mountain support scrub brush and grasses. The mountain was named for J. M. Talley, who settled in the area in the early 1900s.