NO. 1867 AMERICAN FERNS — CHRISTENSEN 385 



versus basin gradatim attenuata, versus apicem breviter acuminatum 

 brevius attenuata, firmo-herbacea, obscure viridi, rachi grisea, pilis 

 patentibus hirta et squamis brunneis crispatis (maxime in parte 

 inferiore) squamosa, bipinnatifida. Pinnis ca. 20 utroque latere, 

 inferioribus oppositis, 4-5 jugis sensim reductis, infimis i cm. longis 

 et latis, superioribus alternis, sessilibus, maximis 8-10 cm. longis, 

 2 cm. latis, lineari-oblongis, versus apicem integrum breviter acumi- 

 natis, ad basin aerophoro magno acuto nigro instructis, supra ad 

 costas late sulcatas ac inter venas pilis adpressis setosis, subtus ad 

 costas costulasque pilis patentibus hirtis, ad alam 2 mm. vel ultra 

 latam pinnatifidis. Laciniis approximatis, sinubus angustis acutis 

 separatis, ca. 15 jugis, 4-5 cm. latis, patentibus vel paulum obliquis, 

 obtusissimis, integris. Venis simplicibus, 6-7 jugis, distantibus. 

 Soris parvis, medialibus ; indusiis parvis, ciliatis, mox evanidis. 



This new species stands next to D. Germaniana, but is consider- 

 ably different in its scaly rachis, its differentiated pubescence, and 

 its distinct, setose indusia. In the system adopted in my "Revision" 

 the species must be placed between D. Germaniana and D. Morits- 

 iana. 



DRYOPTERIS DEMERARANA (Baker) C. Chr. 



Polypodiuni demeraranum Baker, Timehri 5:214. 1886; Trans. Linn. Soc. II. 



Bot. 2: 290. 1887. 

 Dryopteris demerarana C. Chr. Index Fil. 261. 1905. 



British Guiana: Mount Roraima, old Cath, im Thurn 356; (type num- 

 ber). 



A species of the group of D. pachyrachis, but having the leaf more 

 abruptly reduced below, about as in a species of the group of D. 

 Sprengelii. 



Reduced pinnse about 4- jugate, at distances of 4-5 cm., auriculi- 

 form. Stem at base with brown scales more than i cm. long, up- 

 wards like the rachis with a dense and coarse gray pubescence, 

 intermixed with a few linear brown scales, especially along the 

 rachis. Lower pinnse subopposite, upper ones alternate, sessile, 

 10-12 cm. long by 2.5 cm. broad, thin, the upper side along the costas 

 densely setose, between the veins with fine, scattered, hamate hairs, 

 the under side setose along the costse and veins, almost glabrous 

 between the veins. Segments slightly oblique, subacute or roundish 

 at the apex, entire, 3.5-4 mm. broad, rather close, with subacute 

 sinuses between ; basal segments equal in size, or the upper one 

 slightly reduced. Veins all simple. Sori exindusiate, near the edge. 

 Sporangia glabrous. 



