882 G. SKOTTSBERG 



mon in the closed forest and on the banks of well-watered ravines from Valle 

 Frances to Villagra and ascends to the lofty ridges on Masafuera; in favourable 

 situations the fronds will reach a length of i m. Pteris berteroana, one of the 

 finest ferns in the islands, with fronds to i m tall and more, thrives in the deep 

 shade and is found on many places on both islands (PI. 113). A much rarer, but 

 just as large fern is Pteris seviiadnata Phil., restricted to the fog region of central 

 Masatierra above 500 m and reported from the forest patch on the summit of 

 El Yunque; on Masafuera it also occurs in the Alpine region, where it is stunted. 

 Pteris chilensis Desv. is of smaller stature than the other two, scattered through 

 the wooded country of Masatierra but rare on Masafuera. Among these large and 

 conspicuous ferns, the endemic BlecJinuni loiigicauda C. Chr. stands first. It is 

 restricted to the canyons in Masafuera, where it adorns the wet cliff walls; see 

 p. 28 — 29 and PI. 5, this vol. no. i. 



Among the small species of the forest floor, Aspleniuni dareoides Desv. and 

 niacrosorum Bert. ex. Colla (1 c, PI. i: 2) have been mentioned already. They occur 

 on both islands, where the latter is endemic. The same holds good of the elegant 

 A. stellatum Colla with frond tips proliferous. BleclLnmn valdivieiise C. Chr., also 

 found in the Alpine region of Masafuera, is easily known by its reproduction by 

 subterranean runners and by its very dark colour. 



As we have seen above, a considerable number of ferns inhabits the high- 

 lands of Masafuera. Like some of the Hymenophylla, the rare Gleichcnia qiiadri- 

 partita (Poir.) Moore is restricted to high altitudes on Masafuera and was not 

 seen below 11 50 m. The two club-mosses, Lycopodium scariosuni P'orst. (gayanum 

 Remy) and DiagelliDiicuiii Sw. have the same distribution as Gleichejiia quadri- 

 partita. 



Filmy ferns. 



In Juan Fernandez, the HymenopJiyllaceae are represented by i 5 species, Hy- 

 nienoglossuui cruentmn (Cav.) Presl, 10 species of Hy})ienopliyllu)>i, 3 of TricJio- 

 maiies, and Serpyllopsis caespitosa (Gaud.) C. Chr., all of them being more or less 

 strictly confined to moist, shady places in the montane region. Hymenoglosstnn 

 (PI. i: I, this vol. no. i) is scarce on Masatierra and rare on Masafuera. Of //>'- 

 menophylliim, cuneatian Kze (p. 9, fig. 3) and plicatum Kaulf (dichotomum auctt. 

 non Cav.) are common and physiognomically important; less frequent, but not 

 very rare on Masatierra, is H. ferrugi-neum Colla. The endemic H. rugosum C. 

 Chr. et Skottsb. (p. 12, fig. 4), known by its bronze-green colour, is scattered over 

 both islands, H. tortuostan Hook, et Grev., once reported from Masatierra, is rare 

 on Masafuera, H. falklandicum Bak., pectinatum Cav. and secundum Hook, et 

 Grev. only found on Masafuera, H. secundum in a single locality, about 1350 

 m above sea-level {pectinatum recorded once for Masatierra, but never found 

 again). 



The largest species in Juan Fernandez, and probably one of the largest in 

 the genus, is H. fuciforme Sw., restricted to the montane forests in the eastern 

 half of Masatierra (Fig. 30); longest frond measured, 82 cm. Similar to this, but 



