454 A NATURALIST ON THE "CHALLENGER." 



reefs are two larger islands named Wild Island and Dentre- 

 casteaux Island, the latter being nearer to the anchorage. 

 These were the only two islands seen by ns to be inhabited. 



The land surface in the vicinity of Nares Bay, consists of a 

 series of low irregular ridges rising one above another, with 

 wide flat expanses at the heads of bays on the coast, which are 

 scarcely or not at all raised above sea-level, and thus are in a 

 swampy condition. The mountains appear, from their form, to 

 be volcanic ; and it is probable that the obsidian used by the 

 natives for their spear-heads is procured in them. A trachytic 

 lava was found to compose one of the outlying islands ; and a 

 similar rock was observed on the mainland where it commenced 

 to rise. A platform of coral-sand rock forms the coast-line of 

 the main island in many places ; and a similar rock is the only 

 component of most of the small outlying islands. 



From the position of the Admiralty Islands with regard to 

 the equator, their climate is necessarily an extremely damp one. 

 A great deal of exceedingly heavy rain fell during the stay of 

 the " Challenger." Rain fell on five days of the seven, during 

 which we were at Nares Anchorage, the total fall being 1-66 

 inch. The temperature of the air ranged between 86° and 

 75° F., the mean of maximum and minimum observations 

 being about 80° F. ; and the air was loaded with moisture. 

 Dense clouds of watery vapour hung about the forest-clad 

 ranges, keeping the mountains most frequently concealed ; 

 and in the evenings clouds of mist hung about the lower 

 land, looking like smoke rising from between the densely- 

 packed trees. In a bay some miles to the eastward of the 

 anchorage of the " Challenger," the mouth of a small river, 

 apparently the outlet of the drainage of the mountains on this 

 side, was found, and also a very small brook; but running 

 water was not elsewhere observed, and the rain probably drains 

 to a large extent into the swamps. 



The main island, as viewed from seawards, is seen to be 

 densely wooded everywhere. Along the summits of the ridges 

 Cocoa-nut Palms show out against the sky, accompanied by 

 Areca Palms, as can be made out on a nearer view. The 

 general dark-green mass of vegetation on the hill-sides is fes- 



