DERIVATION OF THE FLORA AND FAUNA 233 



Catagoniopsis Broth. Monotypical, related to Catagonium (S. hemisph.) 

 berteroava (Mont.) Broth. Centr. Chile. — Mt. 



Hypnodendraceae. 



Hypnodendron Lindb. (28). Chile (2), IndomaL, Austral., Polyn., Hawaii. 

 microstictum Mitt. Chile. — Mf. 



Polytrichaceae. 



Oligotrichmn Lam. et DC. (13). Widely scattered: 2 W. N. Amer., 4 Chile; single 

 sp. Braz., trop. Andes, Arct.-alp., Eur., bor.-circump. 



caiialiculatum (Hook.) Mitt. var. The typical sp. in S. Chile. — Mf. 

 Psilopilum Brid. (17). A bipolar genus, tricentric in the S. hemisph. 



antarcticu7n C. M. Boliv., Fueg., Falkl., S. Georgia, Kerguel. — Mf. 

 Polytrichadelphus (C. M.) Mitt. (22). Centering in the Andes (17), i W. N. Amer., 

 I Braz., 2 Magell., i subant.-bicentric. 



magellanicus (L.) Mitt. Patag., Fueg., Falkl., E. Austral., Tasm., N. Zeal., Auckl. 

 and Campb. Is. — Mf. 

 Dendroligotrichum (C. M.) Broth. Monotypical. 



dendroides (Brid.) Broth. Peru, S. Chile south to Fueg., N. Zeal. — Mf. 



The geographical distribution of the mosses is less well known than of the 

 vascular plants, and some of the species now considered to be endemic in Juan 

 Fernandez will perhaps be discovered on the mainland. No specialist ever visited 

 the islands, where most likely further species, endemic or known from elsewhere, 

 will be found. Species now only recorded from Masatierra may be found onMasafuera, 

 and vice versa. 



The 131 species of mosses hitherto recorded from Juan Fernandez belong to 65 

 genera (2: i), all known from elsewhere; 48 species (36.6%) are endemic, a high 

 figure in a spore-bearing group, higher than for the Pteridophytes (34%). On Masa- 

 tierra 84^ were collected, 50 of these (38.1 %) not found on Masafuera, where 81 

 were recorded, of which 47 (35.9 %) are restricted to this island; 34 (26 %) are known 

 from both islands. No mosses have been reported from Santa Clara. 



The mosses are less evenly distributed than the ferns, presenting a higher 

 degree of local endemism, but this may be due to insufficient knowledge of their 

 distribution. Endemics are more local than non-endemics; of the former (48), 24 

 (50%) are only known from Masatierra, and 16 (33.3 %)only from Masafuera, 8 (16.7 %) 

 being found on both islands; of the non-endemics (83), 26 inhabit Masatierra (31.3 %), 

 31 Masafuera (37.4%) and 26 (31.3 %) both islands. Endemics are proportionately 

 more numerous on Masatierra, where 32 species or 38 % are endemic; the figures for 

 Masafuera are 24 and 29.6. It is remarkable that all the 8 species of Thamnium 

 are endemic on Masatierra. 



For two reasons it is a difficult task to segregate with sufficient accuracy the 



1 Brotherus p. 420 records Rhacomitrium subnigritum from both islands, but the locality 

 quoted for Masatierra is situated on Masafuera. 



