26o CORALS AND CORAL LSLANDS. 



barriers. The reefs of Tahiti extend in some parts a mile from 

 the shores. Tetuaroa, to the north of Tahiti, and Tubuai, near 

 Bolabola, are lagoon islands. Maitea, east of Tahiti, is a sugar 

 loaf truncated at summit, four miles in compass, and is said 

 by Forster to have an encircling reef 



South of the Society Islands, near 25° S., is Rapa, which 

 is represented as a collection of rugged peaks v/ithout coral 

 shores. The Rurutu and Hervey Islands, ju§t north-west of 

 Rapa, have coral reefs fringing the shores. There is no evi- 

 dence of recent volcanic action among them. Some of them 

 are elevated coral islands, as Mitiaro, Atiu, Mangaia and Mauki, 

 and also, according to Stutchbury, Rurutu. Okatutaia is a low 

 coral island but six or seven feet out of water. 



Between the Paumotus and the longitude of Samoa are 

 numerous small islands, all of coral origin. 



The Samoan or Navigator Islands have extensive reefs. 

 About Tutuila, owing to its abrupt shores, they are some- 

 what less extensive than around Upolu, and about Savaii they 

 are still smaller, as already explained. The influence of abrupt 

 shores may also be seen in some parts of Upolu ; for example, 

 to the west of the harbour of Falifa, where, for several miles, 

 there is no reef, except in some indentations of the coast. 

 Manua is described as having only shore reefs. 



The Tonga Islands, south of Samoa, for the most part 

 abound in coral reefs, and Tongatabu and the Ilapai Group 

 are solely of coral. Eoa is a moderately high island, with a 

 narrow reef. Tafoa, an active volcano, and Kao, an extinct 

 cone, are without reefs. Vavau, according to Williams {Miss. 

 Enterprises^ p. 427, Amer. ed.), is an elevated coral island. 

 Pylstaarts, near Eoa, is a naked rock, with abrupt shores, and 

 little or no coral. Sunday Island, farther south (29"" 12' S.), is 

 beyond the coral-reef limits. 



North of Samoa are several scattered islands of small size, 

 all of coral. 



The Feejee^ Group, already sufficiently described, abounds 

 in reefs of great extent. There are no active volcanoes, and, 

 where examined, no evidence of very recent volcanic action. 



