131 183 
D. augescens is a very critical species, very well described and figured by 
Kunze. It is almost exactly intermediate between D. normalis and D. serra, agreeing 
with both in the creeping rhizome and the shape and colour of the scales. In 
general habit it resembles D. normalis, from which it differs by 1) the firmer la- 
mina, which rather suddenly narrows upwards into a pinnatifid apex but not having 
a distinct terminal pinna as D. serra, 2) the narrower pinnz, about 1 cm broad, 
the lower ones a little narrowed towards the shortly auricled base, 3) the presence 
of small, hairy scales on the coste beneath, exactly resembling those of D. serra, 
similar scales are often found on the rachis, 4) the very acute, oblique or patent 
but not falcate, oblong-triangular segments with somewhat revolute edges, and 
5) by the veins being prominent beneath. — From JD. serra, which it resembles 
very much in pubescence by hairs and scales, it differs by 1) the shorter pinnze, 
which are rarely more than 12 cm long, less acuminate and more deeply cut, 
2) the want of a distinct terminal pinna, 3) the lower basal segment of most pinnz 
not adnate to rachis, 4) thinner texture and less prominent cost, 5) the non-falcate 
segments, and 6) the basal anterior vein only running to sinus, the posterior one 
generally reaching the margin a little above the sinus. 
— Stipes slightly scaly downwards, rather slender, 30—50 cm long; lamina of 
the same length, fresh- or darkgreen; costz: above more or less pubescent, the 
upperside elsewhere glabrous; underside not glandulose. Veins about 8 to a side; 
sori a little supramedial, furnished with persistent, setose indusium. 
The following specimens are typical: 
Cuba: Prov. Habana, Nazarene, BAKER nr. 1893 (W); Puntes Grandes, H. Leon nr. 165 (W); near San- 
tiago de las Vegas, Witson nr. 444 (W) — San Antonio de los Banos, Baker & O'Donovan 
nr. 4132 (W) — Tabureto, E. Orro nr. 215 (B) — Prov. Pinar del Rio, Guanajav, EARLE et 
Wirsow nr. 1511 (W); near Caiamito, ParwER et RirEv nr. 705 (W) — Isle of Pines, PALMER 
et Rivey nr. 1120 (W). 
Mexico: San Luis Potosi, near Rascon, Epw. PALMER nr. 661 (W); near Tancanhuitz, C. et E. SELER 
nr. 695 (B); ScHAFFNER sine num. (B) — Jalisco, near Guadalajara, Epw. PALMER nr. 76 (W) 
— Colima, San Marcos, M E. Jones nr. 529 (W) — Tamaulipas, near Victoria, Epw. PALMER 
nr. 569 (W). 
Costa Rica: Cartago, J. J. Coopzn, ed. J. D. S. nr. 6050 (W). 
The following specimens from Bahama Islands resemble very much D. 
serra in size and are perhaps belonging to that species; still they agree best with 
D. augescens in most differential characters. 
Andros, Nicols, Town, J. and A. Norrurop nr. 441 (B); Providence, Nassau, 
J. and A. NonrHnoP nr. 173 and 240 (B); Rawson W. Rawson (B); EGGERS 
nr. 4178 (H). 
While the Mexican specimens enumeraled above are very typical some other 
specimens are scarcely to distinguish from D. normalis var. Lindheimeri ; these spe- 
cimens again are intermediate between the type and the larger, common Mexican 
fern registered in my Index as D. Feei C. Chr. It is impossible to me to distin- 
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