Subgenus 7. Cyclosorus (Link) C. Chr. 
Biolog. Arbejder tilegnede Eug. Warming pag. 81. 1911. 
The American species of this subgenus are all bipinnatifid and closely related 
to each other. The rhizome is erect or creeping, clothed with lanceolate or ovate, 
as a rule hairy and entire scales. Lamina with a broad base or shortly narrowed 
downwards. Aérophore none; under-surface often glandular, especially on the 
ribs. Most species rather pubescent by simple, unicellular hairs, only in some few 
species the longest hairs consist of 2—3 cells, or some of the hairs of the rachis 
are forked from the very base (f. inst. in certain forms of D. oligophylla). In some ' 
species rachis and the coste beneath bear some few minute, lanceolate scales, 
which often bear long hairs along the edges. Veins simple, the basal ones either 
connivent to sinus, where they meet or more often are separated by a cartilagineous 
membrane that can protrude between the segments as a projecting apophysis, or 
truly united in the leaf-tissue and sending a branch to the sinus. Sori often large, 
indusiate. Indusium reniform, generally persistent and pilose, often also glandular. 
Sporangia glabrous (D. Martini excepted, which see). 
Cyclosorus is allied to Lastrea and Steiropteris. Its best characters are venation, 
non-decrescent lamina and large, persistent indusia. In America it is represented 
by a dozen species, most of which are very variable and connected by inter- 
mediate forms. The subgenus is as a whole the most difficult to deal with and 
several of the species can be distinguished from each other by certain characters, 
which can not be explained by words or figures but which are easily observed by 
the trained eye. Two of the species, D. mollis and D. gongylodes, are not exclusively 
American but widely distributed in the Old-World, where the subgenus is richly 
developed. 
Keine 
Lamina pinnate only, see D. pusilla nr. 54 under § Lastrea. 
Lamina bipinnatifid : 
1. Basal tertiary veins free or connivent to sinus, not normally united 
in the leaf-tissue. 
2. Rhizome erect. Rachis not scaly. 
3. Basal scales broad, thin, yellowish or brown, as a rule glabrous. 
Lower pinne not reduced. Basal segments both prolongated 
andaparallelitosrschis PE ccc 190. D. patens (Sw.). 
3. Basal scales narrow-acuminate, ferruginous, glossy, hairy. Lower 
pinnze somewhat reduced. Basal segments (at least the posterior 
one) not conspicuously prolongated. 
4. Pinnz 4—6 em long by 1 em broad, rather firm. 191. D. Goedenii Ros. 
