Se 
CHRISTENSEN, ON SOME SPECIES OF FERUS COLLECTED. 31 
4. var. Dusenii (Christ). fig. 4 d—i. 
Syn. Hymenophyllum Dusenii Christ apud DUSÉN: Sven- 
ska Expedit. till Magellansländerna. Wissensch. Ergebnisse 
3: 242. 1899 (t. specim. orig.). 
Rhizome very slender; leaves !/—3 cm. long with a pro- 
portionally long slender stipe, generally more narrow below; 
pinne few, (3—4 to a side) distant, exactly spathulate, ascen- 
ding, their base cuneate, decurrent on the rachis on the 
lower side, almost cut away on the upper one; lower pinns 
often dwarfed, upper ones 1—1!/» mm. broad below the apex; 
Fig. 4. Serpyllopsis caespitosa. a—c, f. typica: a apex of stem, showing bi- 
serial leaves '/ı; b single leaf with definite growth; c do. with indefinite 
growth, 7/1. — d—i var. Dusenii: d 'A; e single leaf ?/ı; f—h dwarf form '/ı; 
i terminal sorus enlarged. 
hairs few; sori only seen in a small form (fig. 4 f, i), large, 
single on the apex of the rachis, scarcely two-lipped, the 
mouth entire. 
Tierra del Fuego: mountain above the Cami Camp, 
alpine region, 10. 3. 1908, nr. 218. 
This variety looks very distinct, but its very slender 
rhizome and stipe and peculiar habit are evidently due to 
its growing-place between dense masses of mosses (Poly- 
trichum). It is connected with the type by some forms of 
var. elongata. Dr. CHrist’s description agrees badly with 
our plant, which, however, is exactly the same form as the 
type-specimen of H. Dusenii in Naturh. Riksmuseum. 
