Proc. Amer. Acad. Arts 17: 375. 1882.
Plants 40–90 cm. Leaves: basal 4, blade lanceolate to elliptic, 70–130 x 35–50 mm, 2-pinnatifid, margins of adjacent lobes nonoverlapping or slightly overlapping distally, serrate, surfaces hispid; cauline 7, blade lanceolate to elliptic, 20–90 x 8–35 mm, 1-pinnatifid or 2-pinnatifid, margins of adjacent lobes nonoverlapping or slightly overlapping distally, serrate, surfaces hispid. Racemes simple or paniculate, 1–4, exceeding basal leaves, each 3–30-flowered; bracts trullate, 8–13 x 7–10 mm, undivided or pinnatifid, margins serrate to 2-serrate, surfaces hispid. Pedicels 1–3 mm. Flowers: calyx 5–12 mm, hispid-glandular, lobes 5, narrowly triangular, 3–4.5 mm, apex entire or dentate, glabrous; corolla 14–19 mm, tube yellow, 8–10 mm; galea yellow, apically sometimes tinged red, 6–8.5 mm, beakless, margins entire medially, 1-toothed distally, apex arching slightly over abaxial lip; abaxial lip yellow with apex sometimes tinged red, 7–7.5 mm.
Phenology: Flowering Jul–Sep.
Elevation: 100–300 m.
Discovered in 1880, and at one time believed extinct, Pedicularis furbishiae was rediscovered in 1974 during an environmental impact survey for a proposed dam on the St. John's River and thereafter was placed on the Federal Register under the Endangered Species Act (L. W. Macior 1981). Metapopulation dynamics suggest that an ecologically intact watershed is required for long-term persistence (E. S. Menges 1990). A recovery strategy has been adopted for this species in New Brunswick (Furbish's Lousewort Recovery Team 2006; Environment Canada 2010). Pedicularis furbishiae is in the Center for Plant Conservation’s National Collection of Endangered Plants.