94 42 



hairy and more or less scaly by filiform scales, which are distinctly and sharply 

 toothed by claw-shaped teeth; the cell-walls very dark and thick, the lumina 

 small (lig. 3"'). Under-surface often glandular. Segments patent or a little oblique, 

 with the edges parallel, the apex truncate or bluntly rounded, entire or finely 

 toothed, not mucronate. Veins 10 — 15, oblique. Sori infra medial, rarely almost 

 medial, furnished with a persistent, reddish, glabrous or slightly ciliate and glan- 

 dulose indusium. 



From D. falciculata the present species differs by more veins in the patent, 

 obtuse segments, inframedial sori and the different shape of the scales; from D. 

 siibmurginalis it differs by the dark colour of the lamina and scales, obtuse seg- 

 ments, inframedial sori and persistent indusia. 



The specimens examined can be referred to two forms : 



1. forma isabellina (Fée). 



Scales of rachis and costæ few and small, very like those of D. suhmarginalis 

 f. lenuifolia but darker and more distinctly toothed (fig. S^"''); rachis, costæ and 

 both surfaces hairy by scattered, red, deciduous hairs. Pinnæ 2'/2— 3 cm broad; 

 segments rather oblique, finely toothed or often deeply serrate in the lower pinnæ. 

 Veins 10—12, forked in the serrate segments; sori often nearly medial. — Stipe at 

 base with a dense mass of soft, reddish scales. 



This form, lo which the original specimen of A. ctenitis Link seems to belong, 

 is very closely related to D. submarginalis f. tenuifolia, from which il differs mainly 

 by colour, structure of the scales and the persistent indusium. 



Brazil: Rio, Glaziou nr. 2368 (C, H, Rg), 2371 (H), 2372 (H, Rg). 



MiiKis ("leraes: Lagoa Santa, Warming (H) — Caldas, Lindberg ur. 557 (B), Mosen nr. 214G pt. 



(B, Rg). 

 Sao Paulo: Tieté, Gerder nr. S4a (Rl — Toledo, Schnapp nr. 43 (C). 



2) forma aniaurolepis (Fée) — (A. amaurolepis Fée, A. squamigerum Mett., Lastrea 

 distans Brack.) 



Larger and more scaly than the preceding form, the scales larger and darker. 

 Costæ beneath flat and sulcate, furnished with two kinds of scales: 1) lateral ones, 

 which are red-brown and patent (fig. ',V^^}, and 2) frontal ones, which are adpressed 

 and almost black (fig. 3^^''^). Both surfaces generally glabrous. Pinnæ 4 cm broad, 

 the segments close, patent, obtuse; veins about 15; sori inframedial. — Stipe at 

 base apparently without a dense mass of soft scales. 



Between this excellent form and f. isabellina numerous intermediates are to 

 be found, the two forms described being the two extremes of D. ctenitis. 



Brazil: Rio, Glaziou nr. KiSO, 237(1 (H), Mosen nr. 100 (Hg. S|, Martius iHb. Fl. Brazil nr. 324 (B), 



and others. 

 Minas Geraes: T. de Moura (B). 

 Bahia: du Pasquin 1851 (B). Luschnath nr. 118 (Bj. 



