THE VEGETATION OF THE JUAN FERNANDEZ ISLANDS 933 



Possibly this is what happened. I should add that the goats do not seem to 

 touch either the ferns or the pangue leaves. Perhaps some of the cespitose na- 

 tive grasses and sedges and mat-forming herbs were more widely spread; other 

 species, more palatable to the goats, may have become extinct. Phoenicoseris 

 regia, Rohiiisoiia JMasafucrae and Raninuulus caprarvvi are on the verge of ex- 

 tinction. 



The vegetation along the streams and cascades is characterized by the ab- 

 sence of the leading species in Masatierra, Cladium scirpoideiim and Cardainhie 

 flaccida. Gunnera peltata is replaced by G. Masafuerae and Cladium^ in a 

 way, by Blechniun longicatida. Mhmdus glabratus, not found on Masatierra, 

 has to be added. A few hydrophilous bryophytes are common. This vegetation 

 is at its best in the deep canyons from Ouebrada de las Casas south to Q. del 

 Varadero. These magnificent gorges constitute one of the most interesting feat- 

 ures of Masafuera. In the U-shaped part trees and shrubs have colonized the 

 ledges and ravines on the vertical walls; grasses, ferns and other herbs of the 

 forest floor cover the rock faces. I have not tried to co-ordinate these sociation 

 fragments with the forest communities but prefer to treat the vegetation of the 

 canyons under a separate heading. 



The Stations. 

 The Forest region. 



The luma-forest of Masafuera diff"ers from the Masatierran forest in some 

 respects. NotJiomyrcia is replaced by Myrceugenia Schuhei, which has a lighter 

 colour, Fagara externa does not attain the large dimensions of F . mayii, SopJiora 

 masafucrana was not seen in the forest and is much less common. Coprosnia 

 pyrifolia, Driviys and RJiapJiithauinus are shared by both types. As the species 

 often forming a dense undergrowth on Masatierra are absent and, with one excep- 

 tion [Berberis corymbosd), not represented by vicarious species [^B. masafuerajia 

 is rare and was not observed in the forest), the Masafueran forest is less dense and 

 very monotonous. Ferns and other cryptogams are abundant, but several of the 

 conspicuous species are wanting. The delicate Dysopsh, quite important in the 

 dark, humid woods of Masatierra, is absent. The scarcity of rosette trees was 

 already pointed out. With increasing altitude the epiphytes and the filmy ferns 

 increase in number, and WeymoutJiia makes its appearance. 



The lower montane forest. 



57. (20.) My rceuge?iia- Coprosnia pyrifo/ia-Sociatlon. Quebrada de la Loberia 

 Vieja, c. 280 m, 17/2 1917. Thin, very stony soil mixed with twigs and dried leaves. 



IV^s-i Coptosma pyrifolia 2 



Myrceug-efua Schulzei 4 Fagara externa i 



III (rarely over 2 m) ^^- 3 



Myrceugenia 4 Copros?na 4 



Gunnera Masafuerae i 



