Part 1, 1909] GLEICHENIACEAB 55 
ous spreading castaneous articulate hairs; primary leaf-axis at first rigidly erect, stout, 24 
mm. in diameter, firmly terete, light-brownish or somewhat stramineous, elongate; pri- 
mary lateral branches several pairs, opposite, distant, repeatedly pseudodichotomous, a 
secondary leaf-axis invariably wanting, the internodes unequal, naked; primary internodes 
usually 6-8 (rarely 18) cm. long, the others successively shorter, the nodes stipulate at the 
upper side (the stipules narrow and subentire to deltoid and deeply pinnatifid), at the 
lower side provided with spreading or usually deflexed oblong-linear to lanceolate-oblong 
pectinate accessory pinnae, the larger ones 8-13 cm. long, up to 2.5 cm. broad, those of the 
upper nodes gradually smaller; pinnae sessile, ascending or somewhat divergent, variable, 
12-23 cm. long, 2-6 cm. broad, attenuate, fully pectinate (the outer basal segments often 
prolonged and deeply pinnatifid), straight, subfalcate or slightly flexuous, linear to oblong- 
lanceolate, cut nearly to the rachis, glabrous throughout, light- or yellowish-green, glau- 
cous below; segments variable in size, linear-oblong to linear, retuse, connected by a nar- 
row wing at the dilatate base, the margins strongly revolute, sometimes meeting at the 
middle of the segment; veins 2-4-forked, close, elevated above, below deeply impressed ; 
sori numerous if present, multisporangiate, borne upon the distal and sometimes addition- 
ally upon the proximal veinlet of each group. 
TYPE LOCALITY: Brazil. 
DISTRIBUTION: General in the Greater Antilles, not common in the Lesser Antilles; on the 
continent extending from southern Mexico (rare) to Brazil, mainly at low elevations, rarely 
ascending to 1500 meters. 
ILLUSTRATIONS: Mart. Ic. Crypt. Bras. p/. 60, f. 1; Sturm, in Mart. Fl. Bras. 12: pl. 17. 
3. Dicranopteris pectinata (Willd.) Underw. Bull. Torrey 
Club 34: 260. 1907. 
Mertensia pectinata Willd. Sv. Vet.-Akad. Handl. IT. 25: 168. 1804. 
Mertensia brasiliana Desy. Ges. Nat. Freunde Berlin Mag, 5: 329, 1811. 
Mertensia canescens Kaulf. Enum. Fil. 38. 1824. 
Mertensia emarginaia Raddi, Pl. Bras. 1: 72. 1825. 
Gleichenia nitida Presi, Rel. "Haenk. 1: 70. 1825. 
Gleichenia brasiliana Spreng. Syst. Nat.4: 27. 1827. 
Meritensia elata Desv. Mém. Soc. Linn. Paris 6: 201. 1827. 
Gleichenia Hermanni Hook. & Grev. Ic. Fil. 1: Al. 14 (excl. syn.). 1827. Not G. Hermanni 
R. Br. 1810. 
Mertensia nitida Presi, Tent. Pterid. 51. 1836. 
Gleichenia Hookeri J. Smith, Lond. Jour. Bot. 2: 381. 1843. 
A laxly ascending diffuse plant, forming extensive thickets; rhizome wide-creeping, 
3-5 mm. in diameter, light brownish-castaneous, conspicuously scabrous from the persistent 
bases of numerous deciduous castaneous articulate hairs; primary leaf-axis at first erect, 
stout, 3-6 mm. in diameter, stramineous to light-brown, terete, elongate, eventually declin- 
ing ; primary lateral branches several pairs, opposite, stipulate, repeatedly and unequally 
pseudodichotomous, a falsely sympodial naked flexuous secondary axis formed by the alter- 
nate production of the unequal secondary branches, the shorter ones bearing a pair of pinnae 
or again unequally forked and bearing two pairs of pinnae; lower nodes of the lateral 
branches inconspicuously stipulate; included terminal bud of each dichotomy invariably 
abortive; pinnae variable, 10-25 cm. long, 1.5-6 cm. broad, sessile, fully pectinate (the 
outer basal segments often somewhat prolonged), subfalcate, unequally lanceolate or 
oblong-lanceolate to linear, attenuate, glaucous below (sometimes conspicuously so), glabrous 
to glabrate or (especially in narrow forms) having the costae and veins sparsely clothed with 
deciduous stellate or substellate slender ferruginous scales ; segments variable in size, oblong 
to linear-oblong, connected by a narrow wing; veins 3-5-forked, slightly elevated below ; 
sori numerous (or frequently altogether lacking), multisporangiate, nearly medial, invariably 
borne upon the distal veinlet of each group. 
TYPE LOCALITY: Near Caracas, Venezuela. ; ; 
DISTRIBUTION: Of wide distribution in tropical America ; general in the West Indies; on the 
continent extending from Mexico to Ecuador and Brazil. Polymorphic. : : ; 
ILLUSTRATIONS: Sv. Vet.-Akad. Handl. II. 25: pi. 4; Hook. & Grev. loc. cit.; Raddi, loc. cit. 
6. 
