2SS CORALS AND CORAL ISLANDS. 



Aim (Wateoo of Cook) is a raised coral island. Cook 

 {Voy., i. i8o, 197) observes that it is "nearly like Mangaia." 

 The land near the sea is only a bank of coral ten or twelve 

 feet high, and steep and rugged. The surface of the island is 

 covered with verdant hills and plains, with no streams. It is 

 described by Williams in his Missionary Enterprises, Mauke 

 is a low elevated coral island according to Williams, and Mitiaro 

 resembles Mauke. Okatiitaia is a low coral island, not more 

 than six or seven feet high above the beach, which is coral sand. 

 It has a light-reddish soil. 



Rurutu has an elevated coral reef one Jiundred and fifty feet 

 in height, as stated by Stutchbury, and also Williams. Tyerman 

 and Bennet describe the island as having a high central peak 

 with lower eminences, and speak of the coral rock as two 

 hundred feet high on one side of the bay and three hundred 

 on the other (ii. 102). — EUis says that the rocks of the interior 

 are in part basaltic, and in part vesicular lava (iii. 393). 



With regard to the other islands of these groups, Manuai^ 

 Aitutaki, Rarotonga, Rimetara, Tubiiai., and Raivavai, the 

 descriptions by Williams and EUis appear to show that they 

 have undergone no recent elevation. 



d. Tonga or Friendly Islands, and others in their vicinity. 



AH' the islands of the Tonga Group about which there are 

 reefs give evidence of elevation : Tongatahu and the Hapaii 

 islands consist solely of coral, and are elevated atolls. 



Eua, at the south extremity of the line, has an undulated 

 mostly grassy surface, in some parts eight hundred feet in 

 height. Around the shores, as was seen by us from shipboard, 

 there is an elevated layer of coral reef rock, twenty feet thick, 

 worn out into caverns, and with many spout-holes. Between 

 the southern shores and the highest part of the island we ob- 

 served three distinct terraces. Coral is said to occur at a height 

 of thi'ee himdred feet. From the appearance of the land, we 

 judged that the interior was basaltic ; but nothing positive was 

 ascertained with regard to it. 



Tongatabu (an island visited by us) lies near Eua, and is in 

 some parts fifty or sixty feet high, though in general but 



