115 167 



A critical species of doubtful position; provisionally I place it in this section, 

 because it in colour and pubescence best agrees with the other species. Still it 

 lacks aerophores, and the rhizome is described as erect; the vein-like keel is in- 

 conspicuous but present. From the nearest species, D. Leprieurii, it diiTers further 

 by its thin texture, much reduced lower segments of the lower pinnæ, and pube- 

 scence, stipe, rachis, costæ on both sides being long-hairy by patent, grey, pluri- 

 cellular hairs with a few short hairs intermixed. Segments linear, somewhat 

 oblique, acute, connected by a very narrow wing; veins 10 — 11-jugate; sori small, 

 medial, with a small, short-hairy indusium. 



183. Dryopteris Leprieurii (Hook.) O. Ktze. Rev. 3: 813. 1891; 

 C. Chr. Ind. 274. — Fig 21c. 



Syn. Nephrodium Leprieurii Uk. sp. 4: 106. 1862; Hk. Bak. Syn. 266; Jenman, 

 W. Ind. and Guiana Ferns 216. 



Type from French Guiana, Leprieur (Kew! specim. auth. also in B and W). 



The typical form of this species is closely related to D. L' Herminieri, differing 

 from it by its non-reduced lower pinnæ and the basal segments of lower pinnæ 

 being considerably reduced; also it is much larger, lamina '/2 — ^U m long by 

 2'/L' — 3 dem broad, the opposite pinnæ 12 — 15 cm long, 2'/2 — 3 cm broad. In 

 pubescence it agrees with D. L' Herminieri, still the leaf-tissue of both surfaces is 

 finely pubescent by adpressed hairs. Veins 10 — 12-jugate, raised above, the basal 

 ones reaching the margin a little above the sinus; keel inconspicuous in some 

 specimens, distinct in others. Sori medial, indusium large, more or less hairy. 



Jenman (I.e.) describes the rhizome as being erect; unfortunately all the spe- 

 cimens from Guiana seen by me want rhizome, but in the Brazilian specimens 

 are found parts of the rhizome, which appears to have been creeping with 

 scattered leaves. 



D. Leprieurii is apparently a very variable species, at least if the specimens 

 referred to it really belong to a single species. Even the specimens from Guiana 

 vary not a little, and some of them belong perhaps to Nephrodium subfuscum Bak. 

 Syn. Fil. 267. 1967; Jenman, W. Ind. and Guiana Ferns 217; Dryopteris subfusca 

 O. Ktze., C. Chr. Ind. 295 from Cayenne, Leprieur, which I cannot distinguish 

 from D. Leprieurii from the descriptions alone. Jenman says that it is intermediate 

 between N. Leprieurii and N. stipulare f= D. patensj. The type-specimen of it was 

 not found in the Kew Herbarium. 



Besides the authentical specimens of D. Leprieurii I have seen some others 

 from Guiana, f. inst.: Demerara, Jenman (W); Maraval, Bot. Gard. Herb. Trinidad 

 nr. 335 (W). Further I refer here some specimens from Brazil and the central 

 South American Andes, which probably belong to var. ß Hook. spec. 4: 106. 

 They differ from the typical form by more numerous veins (16 — 18 to a side), 

 more deeply incised pinnæ (wing 1 — 1 'a mm broad), large fronds (^/4 — 1 m long, 



22* 



