THE VEGETATION OF EASTER ISLAND 



501 



Campylopiis hygrophilus, an endemic species, is submerged and fills the 

 numerous water-holes. The Scirpetiini reappears round the irregular pools of 

 open water scattered over the bog (distinctly visible on plate 33), and is accom- 

 panied by the same Civnpyiopus, which forms a pure association in the water, 

 corresponding to the hydrophilous Sphag}ia in peat bog depressions elsewhere. 

 I do not know if the water-holes are primary or secondary. 



3. The peat bog. Cainpylopus tiirjicola- As^. Plate 33. 



A sordid green peat cover of unknown thickness, floating on the water. The 

 depth of this j)eat must be considerable. It is wet, but of course not covered 

 with water, and it is firm enough to carry the weight of a man, but there 

 are many treacherous places. Even cattle are reported to have crossed the 

 bog safely. 



Fj Agrostis retrofracia, i Fi Vittaria elongata, i 



Axonopns paschalis, i G Cainpylopus turficola, 5. 



Aspleniiini adiantoides var. squa- 

 niulosuni, I 



On the slightly raised areas Cainpylopus turficola is replaced by a form 

 called f. depaiiperata. Cladonia pityrea f. sorediosa is immixed. 



Ratio Aroi, Jiine 25, igij. Alt. c. 400 m. 



The crater has gentle slopes and is shallow. The lake is probably not 

 deep; it is overgrown with a vegetation less differentiated than in R. Kao. 

 The Scirpetiun does not form a continuous belt. 



1. Scirpus riparius-Kyllinga brevifo Ha- Ass. 



F3 Scirpus riparins var. paschalis, Dryopteris gongylodes, i 



in patches, 5 Polygonum acuminatum, i 



F2 Kyllinga brevifolia, 5 G Mosses not collected. 

 Cyperus vegetus, 2 



2. Campy lopus- Ass. with fairly abundant Agrostis retrofracta. 

 No collections made. 



Rano Raraku, Jiine 2g, igij. 



The crater floor is wide and the lake probably shallow. The water is open 

 with a wide fringe of Scirpus riparins var. paschalis and Polygonum acumina- 

 tum. I do not know why the Campylopus cover is absent here, unless some 

 chemical property of the water is responsible, but this is difficult to believe. 

 The open water was not accessible. 



CONCLUDING REMARKS 

 In order to study the plant communities of Easter Island, poor as they 

 are, more time is needed than was at our disposal, but I hope that at least 

 the main features and the principal associations have been described with fair 



