424 



C. SKOTTSBERG 



towards South America but this is not where we ought to look for the vanished 

 world that could have inhabited a greater and higher Easter Island; rather, we 

 have better look in the opposite direction. 



It is FoRRKsr Brown's merit to have pointed to the large insular world 

 known as Southeastern Polynesia as as important floristic — and, I presume, faun- 

 istic — centre, and from his Flora (jj) and the reports published by members of 

 other recent survey parties, sponsored by the Bishop Museum in Honolulu, the 

 following data were compiled. The Society Islands are excluded and only the 

 angiosperms considered. Included are the Marquesas, Tuamotu and Austral or 

 Tubuai Islands, and the more isolated Rapa (Oparu), Mangareva (Gambler), Pitcairn 

 and Henderson (PLlizabeth) Island. 



The Marquesas Islands are high, 800-1200 m, and belong, to judge from the 

 geology and topography, to the same generation of Tertiary islands as Tahiti, 

 Juan Fernandez, Macaronesia, etc. The Tuamotus proper are atolls. Of the Austral 

 Islands the high basaltic are considered, Rimatara, 95 m, Rurutu, 410 m, Tubuai, 

 400 m, and Raivavae (Vavitao), 440 m; further, the following outlying islands are 

 included: Rapa (Oparo), 640 m, Mangareva (Gambler), 400 m, Pitcairn, 350 m> 

 and Henderson (Elizabeth), an islet of raised coral said to be only 25 m high 

 ( lY f ) but nevertheless the home of an endemic Stvitaliwi (compare Laysan of the 

 Leeward Hawaiian Islands with S. cllipiicuui var. laysanense). The Marquesas flora 

 is considered to be well known and the same may be true of the flora of the 

 otiicr islands, even if no complete lists have been published; I suppose that all 

 the novelties have been described, but my figures for wide-spread species are, 

 perhaps, too low. There is a difference between my figures and those given by 

 Brown, because varieties are counted by him as units equal to species, which 

 e.\[)lains why his figures for the endemics are so high. 



The largest families are Rubiaceae (36), Cyperaceae (25), Compositae (19), 

 lui[)horbiaceae (16), Gramineae (13), Leguminosae (12), and Piperaceae (10). Other 

 large and imj)ortant families, such as Araliaceae, Cruciferae, Ericaceae, Malvaceae, 

 Myrtaceae, Orchidaceae, Sapindaceae, etc., are represented by fewer species. We 

 iiave every reason to believe that the flora has suffered losses after man had 

 taken })ossessic)n of the soil. 



The t(jtal number of presumably indigenous species — many of aboriginal 

 introduction and not few later arrivals have become naturalized — is 282, of which 

 156 are endemic within the area. The genera are 145, of which only 3 are endemic 

 according to Brown. The ratio species : genus is almost 2:1. No genus is very 

 large, the Largest is Psychotria with 12 sjjecies, and 10 have from 5 to 10 species 

 each. The distribution of the species and the number of local endemics are indi- 

 cated in Table VIII. The figures do not pretend to be exact. 



A large proportif)n of endenfics and of woody, arboreous or fruticose species 

 — suffruticose excluded — are characteristic of oceanic floras of considerable anti- 

 c}uity. Of the 156 endemic species 113 (72.4%) are woody, of the 126 found 

 elsewhere 69 (54.8 %). The herbaceous species are, with very few exceptions, peren- 

 nial. Systematically isolated tyi)es are few, and even the Marquesas Islands can- 

 not, in this respect, be compared with either Hawaii or Juan P^ernandez. 



