82 30 



Specimens seen: 

 French Guiana, Leprieur nr. 42 (C, W); Rich (CC); — Deraerara, Jenman (B, C, W). 

 Colombia, Cauca, Lehmann nr. 3802 (B). 

 Brazil, Para, Approya, J. Huber nr. 753 (C). — Rio, Glaziou nr. 12373 (B, H). 



Polystichum abbreviatum (Schrad.) Pr. (for synonymy see Index Fil. 575, 

 the subspecies excluded) should probably also be placed in this group. It is very 

 closely related to D. sithobliquata, mainly dilTerent by the anastomosing veins. It 

 is known from Brazil and also recorded from Guiana and Ecuador. Besides several 

 specimens from Brazil I have seen one from Colombia, Cordoba, Dagua Valley, 

 30—100 m., H. PiTTiER nr. 529 (W). 



Subgenus 3. CteniUs C. Chr. 

 Biolog. Arbejder tilegnede Eug. Warming, p. 77. 1911. 



A natural subgenus including several species all having an erect or oblique 

 rhizome, which like the bases of stipes is clothed at the apex with a dense mass 

 of scales; these are as a rule very large, toothed at the margin or, more rarely, 

 subentire, their apex very long and hairlike; in some species, f. inst. D. strigilosa 

 Dav., the scales are long and narrow, dark-brown and rigid. — Lamina bipinnate- 

 decompound, as a rule brownish green when dry, membranous or herbaceous, 

 rarely coriaceous, not or a little narrowed downwards, more often deltoid and then 

 the basiscop pinnulæ of the basal pinnæ are more or less enlarged. Rachis and 

 costæ beneath always furnished with many or few scales, which are differently 

 shaped in the different species (see fig. 3). Rarely they are quite entire, generally 

 the margins are toothed, or, as in D. deflexa, long ciliated; always the apex is 

 long and hairlike, and some few long ciliæ are to be found at the cordate base; 

 in some species the base of the scale is buUate or subbuUate. The cells are as a 

 rule large and regular, most often rectangular, the inner cell-walls often very 

 thickened and dark, while the outer ones are always thin and colourless (clathrate 

 scales). The structure and shape of the scales, especially of those of the costæ 

 beneath are important specific characters. — Besides the scales the species are 

 furnished with short, articulate, reddish hairs, which in all species are to be found 

 on the costæ above; they consist of 2—4 short, cylindrical cells separated by dark, 

 thick walls (see fig. 3,i). If hairs occur elsewhere, on leaf tissue, veins or margins, 

 they are generally of the same structure. Short, unicellular hairs I have met with 

 only in two species, D. platyloba and D. leptosom. Some species are glanduloso- 

 pubescent by hairs of a similar structure, but often shorter end ending at a gland. 

 Sessile glands as in species of Lastrea scarcely occur. Aërophore none. — Veins 

 simple or, in some species, forked, never anastomosing, the basal ones reaching 

 the margin above sinus, or, in the less-divided species as D. pedicellata, running 



