THE VEGETATION OF EASTER ISLAND 499 



boulders fallen from tlie walls. The upper parts of this talus are barren, the 

 less coarse particles having been washed down, and the vegetation is the same 

 kind of broken A/icro/i-/>ia- Ass. so often observed in similar places, with the 

 addition of Polypodin))i phymatodes. Lower down, elev. 120—130 m, there 

 must be a good deal of soil among the boulders. Here are old plantations of 

 bananas (PI. 30), naturalized specimens of Broussonetia^ Cordyline etc. and 

 planted trees of Mclia azedarach, Acacia sp. and others. As a result of the 

 nature of the substratum, there is no closed plant cover. The vegetation is a 

 complex of association fragments: carpets of Microlepia and other ferns, with 

 some trees, luxuriant moss-mats, especially in depressions between the boulders, 

 and a mosaic of crustaceous lichens on the stones. This is the richest vege- 

 tation found in the island. 



Microlepia slrigosa-Ass. with scattered trees. PI. 31. 



S Broussonetia pap)^rifera, 1, not over 2.5 m high 

 Triumfetta semitriloba, i, rare 



F3 SopJiora torouiiro, one tree, 1.7 m 



F2 Microlepia strigosa, 4 Dryopteris gongy lodes, I 



PolypodiiiDi phymatodes, 2 » parasitica., i 



Ageratum conyzoides, i Solanum Insulae-Paschalis, i 



Caesalpinia bondiic, a trailing Verbena litoralis, i. 



shrub, I, rare 



On the bark of Broussonetia and Sophora: ArtJioiiia fuscescens and Gra- 

 phis liiieola. 



Vittaria elongata-yioss Ass. 



Fi Vittaria elongata, i 



G Canipyloptis dicranodontioides, C. saxicola, Fabronia niacroblepharoides, 

 MacroDiitriuvi spec , Papillaria pascuana, Rhacopilnm cuspidigerum., 

 • Friillania spec, Lejennia spec. 

 Anaptychia speciosa f. sorediifera, Cladonia pityrea f. sorediosa, Par- 

 vielia reticulata, all whitish. 



Lichen Ass. 



Fi Usnea Steineri var. tincta (yellowish). 



G Buellia Glaziouana (straw-coloured, black fruit), B. stellulata f. proto- 

 thallina (light grey, black fruit), B. spec, (black), Diploschistes anactinus (mouse- 

 grey). Opegrapha paschalis (greenish grey, black fruit), Parnielia reticulata 

 (whitish). 



Rano Aroi, June 2j, ipi/. 



Rano Aroi is a shallow crater without arboreous vegetation. The lower 

 talus slopes, elev. c. 400—420 m, are composed of smaller stones and boulders, 

 and the vegetation more evenly distributed than in R. Kao. Just as in this 

 place, three kinds of associations are distinguished. 



