xix THE PHYSICAL CONDITIONS 209 



since the solitary peak of Savaii in the second-named group, which 

 reaches 5,400 feet, alone represents a high-level area. The uplands 

 of Hawaii that is to say, the elevated region between 4,000 or 

 5,000 feet and 14,000 feet (strictly speaking 13,800 feet) are 

 therefore almost unrepresented amongst the oceanic groups of the 

 South Pacific ; and it is only in the peak of Savaii and in the 

 limited high levels of Tahiti that we would expect to find their 

 conditions reproduced. The great effect that this contrast implies 

 in determining differences between the floras of the Hawaiian, 

 Fijian, and Tahitian regions will become apparent as we proceed 

 in this discussion. 



COMPARISON OF THE CLIMATES OF HAWAII, FIJI, AND 



TAHITI. 



Before comparing the climatic conditions in the three groups, 

 it may first be remarked that since they lie, roughly speaking, at 

 not very dissimilar distances north and south of the equator a great 

 contrast is not to be expected in so far as they agree in elevation. 

 The mean latitudes do not differ greatly, that of Hawaii being 20 

 to 21 N., and those of Fiji and Tahiti both about 18 S. The 

 climate of both groups is tempered by the north-east trade in the 

 one region and by the south-east trade in the other. Still there is 

 a difference in the temperature and dryness of the air which 

 noticeably distinguishes Hawaii from Fiji, and to a less extent 

 from Tahiti. The mean temperature of the Hawaiian Islands 

 would be 74 or 75 ; whilst that of Tahiti is placed at 76 to 77, 

 and that of Fiji at 79. But it is to be observed that to a person 

 residing in Fiji after a residence in Hawaii the climate is perceptibly 

 warmer, more humid, and more enervating. No doubt this is in 

 part connected with the greater dryness of the air in Hawaii, where 

 the average relative humidity at Honolulu is placed at 72 per cent., 

 and it must be much less on the Kona coast on the dry side of 

 the largest island. It is, however, probable that the Hawaiian 

 climate was less dry before the destruction of the forests, and that 

 the contrast with the Fijian climate was then less pronounced. 



The great distinguishing feature, however, of the Hawaiian 

 Islands is to be found in their mountain climate. This is not 

 represented in Fiji, but slightly in Samoa, and to a small extent in 

 Tahiti ; and I will now refer more particularly to this important 

 subject. 



In the uplands of the large island of Hawaii, on the tops of the 

 VOL. II P 



