(Davenport) Nieuwland, Amer. Midl. Naturalist. 1: 226. 1910.
Massachusetts fern, thélyptère simulatrice
Davenport, Bot. Gaz. 19: 495. 1894;
Stems long-creeping, 1.5--3 mm diam. Leaves monomorphic, dying back in winter, often 1 cm or more apart, fertile leaves often somewhat longer than sterile leaves, 25--80 cm. Petiole straw-colored above base, 12--45 cm × 1--3 mm, at base sparsely set with tan, ovate, glabrous scales. Blade lanceolate, 14--35 cm, proximal pinnae largest, or lowest pair slightly smaller, blade tapered gradually to pinnatifid apex. Pinnae deeply pinnatifid to ca. 1 mm from costa, 3--10 × 1--2 cm; segments oblong, somewhat oblique, entire; proximal pair of veins from adjacent segments meeting margin above sinus. Indument abaxially of sparsely set hairs 0.2--0.4 mm primarily on costae, also of yellowish short-stalked glands less than 0.1 mm, blade tissue with numerous reddish to orangish, resinous, shiny, sessile, hemispheric glands; blades adaxially with scattered hairs on veins. Sori round, medial; indusia tan, often glandular; sporangia glabrous. 2 n = 128.
Terrestrial in acid soils of shaded swamps and bogs, frequently associated with sphagnum; 0--100 m; N.B., N.S., Ont., Que.; Conn., Del., Maine, Md., Mass., N.H., N.J., N.Y., Pa., R.I., Vt., Va., W.Va., Wis.