Chapter 18

therefore, probably, they compose an atoll: the two former have been coloured blue, but not the latter.

MENDANA or MARQUESAS Group.—These islands are entirely without reefs, as may be seen in Krusenstern’s Atlas, making a remarkable contrast with the adjacent group of the Society Islands. Mr. F.D. Bennett has given some account of this group, in the seventh volume of the “Geographical Journal”. He informs me that all the islands have the same general character, and that the water is very deep close to their shores. He visited three of them, namely, _Dominicana_, _Christiana_, and _Roapoa;_ their beaches are strewed with rounded masses of coral, and although no regular reefs exist, yet the shore is in many places lined by coral-rock, so that a boat grounds on this formation. Hence these islands ought probably to come within the class of fringed islands and be coloured red; but as I am determined to err on the cautious side, I have left them uncoloured.

COOK or HARVEY and AUSTRAL ISLAND.—_Palmerston_ Island is minutely described as an atoll by Captain Cook during his voyage in 1774; coloured blue. _Aitutaki_ was partially surveyed by the “Beagle” (see map accompanying “Voyages of ‘Adventure’ and ‘Beagle’”); the land is hilly, sloping gently to the beach; the highest point is 360 feet; on the southern side the reef projects five miles from the land: off this point the “Beagle” found no bottom with 270 fathoms: the reef is surmounted by many low coral-islets. Although within the reef the water is exceedingly shallow, not being more than a few feet deep, as I am informed by the Rev. J. Williams, nevertheless, from the great extension of this reef into a profoundly deep ocean, this island probably belongs, on the principle lately adverted to, to the barrier class, and I have coloured it pale blue; although with much hesitation.—_Manouai_ or _Harvey_ Island. The highest point is about fifty feet: the Rev. J. Williams informs me that the reef here, although it lies far from the shore, is less distant than at Aitutaki, but the water within the reef is rather deeper: I have also coloured this pale blue with many doubts.—Round _Mitiaro_ Island, as I am informed by Mr. Williams, the reef is attached to the shore; coloured red. —_Mauki_ or Maouti; the reef round this island (under the name of Parry Island, in the “Voyage of H.M.S. ‘Blonde’,” page 209) is described as a coral-flat, only fifty yards wide, and two feet under water. This statement has been corroborated by Mr. Williams, who calls the reef attached; coloured red.—_Aitu_, or Wateeo; a moderately elevated hilly island, like the others of this group. The reef is described in Cook’s “Voyage,” as attached to the shore, and about one hundred yards wide; coloured red.—_Fenoua-iti;_ Cook describes this island as very low, not more than six or seven feet high (volume i.,