INTRODUCTION xix 



As usual, erosion is very great on the windward as compared with the western side 

 of the mountain. There are a number of constantly flowing streams of considerable 

 size, some almost worthy of the name of river. As on Oahu and in fact on all the 

 islands, the forests have been much denuded, but the central portion of the island is 

 well-wooded. In some parts the vegetation is very varied, but in others at no great 

 distance it is very uniform, and it is quite clear that causes quite apart from age may 

 determine the variety or otherwise of the plants on different islands or on different 

 parts of an island. The elevated plateau of the interior is for a large part of a boggy 

 nature, and forms the main watershed of the island. 



Niihau, the small island west of Kauai and now forestless (as has been already 

 mentioned), was not visited by me. Shells of land molluscs of the genus Carelia 

 have been found in a subfossil state there, indicating no doubt a once heavy forest and 

 considerable moisture. It does not appear that the destruction of the forest has been 

 recent, or that any considerable vegetation of larger growth existed at the time of 

 Cook's arrival at the islands. 



Molokai, Plate VI. East of the south coast of Oahu, and separated from it by 

 a channel of about 25 miles, is the narrow island of Molokai, with an area of 261 square 

 miles. Like Oahu and Maui it is formed of two distinct components, the western 

 mountain or Mauna Loa, with an elevation of nearly 1400 ft., and the larger and 

 more important eastern division with its highest peaks, Olokui 4600 ft. and Kamakou 

 4958 ft. Mauna Loa has for years been used as a sheep-pasture and is now almost 

 denuded of native trees. No doubt before the advent of the white man it was fairly 

 well forested, and the empty shells of dead Achatinellids of the genus Amasira have 

 been found there, sure evidence of a condition of moisture that has passed away with 

 its forest. 



The eastern mountains have also been much denuded of their woods on the 

 leeward slopes and for a large part not much dense forest remains except near the 

 backbone of the mountain, where leeward and windward sides meet. On one large 

 area fairly well covered with forest in 1893, but showing some signs of further 

 deterioration in 1896, I reckoned that between the latter year and 1902 two-thirds 

 or more of all the trees had died. This destruction was due to cattle and an introduced 

 Japanese deer. The latter, indeed, became so plentiful that skilled hunters were 

 brought from California to slaughter as many as possible. Both cattle and deer finally 

 entered the wettest and densest parts of the forest, so that in 1902 the appearance of 

 these was totally different from that which they presented six years previously. The 

 Molokai woods have a fairly varied growth of trees and bushes in some localities, but 

 there is an entire absence of Koa forest, and as the Koa [Acacia kod) is one of the 

 most productive trees for the entomologist, a deficiency of species of insects is natural 

 on this account. Evidently there was once a considerable growth of the allied Acacia 

 koaia or of this and A. koa on the lower slopes, below 2000 ft., but these were at the 



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