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tions upon Hillebriind's flora, Uic only comprehensive book in 

 existence on Hawaiian plants, he stated that of the 850 species 

 of vascular plants in Hawaii, 75% are endemic. Anfl of this 

 number 250 belong to about 40 endemic genera. This high 

 percentage of endemism is due partly to the isolation of the 

 entire group of islands, and partly to the isolation of each 

 island from the other by stretches of ocean 10 to 75 miles in extent. 

 Another factor is the range in temperature from that of the 

 tropics at sea level to that of regions of everlasting snow on the 

 mountain peaks. A third is the range in rainfall from almost 

 nothing in the desert to over 400 inches on the highlands of 

 Kauai. The floral afifinity curiously enough is not with America, 

 the nearest continent, but rather with Indo-Malaysia. 



The variable Mesquite, early introduced by a priest and now 

 spread throughout the arid lowlands, has become of great value. 

 Endemic species of Lobeliaceae are numerous, RoUandia and 

 Clermontia being two of the endemic genera. In areas where 

 the mountains are deeply eroded, the Candlenut tree, .^/^^nV^^ 

 moluccana, is conspicuous by its glaucous foliage, while near the 

 rain-forest grow different Eugenias and Metrosideros. In the 

 rain-forest itself the tree trunks are plastered over with filmy 

 ferns, Ophioderma pendulum, and the epiphytic Lycopodium 

 phyllanthum. In such places also grow remarkable tree violets. 

 Treeferns, such as Cibotntm Menziesii, are plentiful. Their 

 soft, downy ramentum or piilu was formerly used for stuffing 

 mattresses. 



Near Kilauea Volcano a different type of vegetation occurs. 

 Both Psilotums are found here as well as two of the three endemic 

 orchids. Very few Rosaceae appear, the commonest being 

 Fragaria chiloensis and Rubus rosaejolius. Other common plants 

 in the ashfields are Lycopodium cermmm and L. venustulum, 

 Gleichenia, Cyathodes Tameiameiae, and Vaccinium reticulatum 

 or Ohelo berry, which is eaten by the Hawaiian goose. A typical 

 composite of this region is Raillardia scabra, noteworthy for 

 its relationship to a Californian genus. Strange areas in the 

 vicinity are the kipukas or "oases," i. e., regions that have es- 

 caped the numerous lava flows. Here many of the rarest 

 plants may be found. 



In the discussion which followed, Mrs. Britton remarked that 

 it was most interesting to find plants here identical with those 

 in the West Indies, e. g., Psilotnm vudum. 



