114 62 
rich in species occurring in tropical America; each new collection received con- 
tains new forms. As the key in my “Revision” includes 82 species only I have 
worked out an entirely new key including all the species known to me. After the 
key follows a systematical enumeration of all species including descriptions of 
several new species or of species not seen, as I worked out my “Revision”. As 
will be seen the order of the species is not exactly the same as in “Revision, and 
further that I have not arranged the species in sections and subsections. I think 
that my present arrangement is a natural one in that sense that species intimately 
related to each other are placed side by side. It is possible to separate out smaller 
groups of closely related species, but such groups are connected with other groups 
by several intermediate species that a thorough grouping of all the species should 
be very defective. As rather distinct small groups I shall here mention 
1°) the group of D. rudis, which includes the species 151—160 and probably 
others. They are large-grown specics with generally dark-green, coriaceous or papy- 
raceous, more or less hairy but always eglandulose lamina, which downwards is 
suddenly narrowed, the lower 3—5 pinnz being fully abortive and like small warts 
along the stipe; the basal segments of the lower pinne are similarly reduced; aérophore 
present; sori exindusiate. In most species the rhizome seems to be creeping. This 
group appears to be a most distinct one, its species being widely different from 
those allied to D. oligocarpa and D. opposita. Still the difference between these and 
such species as D. Sprengelii and D. Christensenii is only small and these species 
again are closely allied to D. panamensis, D. pachyrachis, D. tablaziensis and others, 
which no doubt are intimately related to D. opposita and D. oligocarpa. On the 
other hand D. rudis and its relatives are connected with the large bipinnate species 
D. pteroidea by a species as D. euchlora, and it is perhaps unnatural to place 
species as D. Thomsonii, D. macradenia in another subgenus, Glaphyropteris, as they 
are as to essential characters very near D. rudis. 
2°) the group of D. cheilanthoides, including the species nr. 165—170. Large 
species of thick texture and numerous veins; glanduliform pinnz as in the former 
group and aérophore as a rule present. Rhizome erect; hairs long, soft, pluri- 
cellular; underside often glandulose and viscid; basal segments of most species not 
much reduced, the lower one often prolongated; sori often indusiate. Species of a 
characteristic texture and colour, which I can not explain. This group is through 
D. limbata and D. consanguinea connected with D. opposita and D. sancta. 
3°) The group of D. rivularioides, including the species nr. 132—137, characte- 
rized by a long-creeping rhizome and occasionally furcate veins. All the species 
are from South-Brazil and adjacent countries. 
4°) The group of D. sancta, including the species nr. 56—62, small species of 
thin texture and often with unequal-sided pinne. 
