STRUCTURE OF CORAL ISLANDS. 197 



by's Island. Great numbers of Birgi (large Crustacea), 

 were burrowing over the island, some of which were six inch- 

 es in breadth. 



Otuhu, Paumotu Archipelago.— 14° 5' S. 141° 31V W. 

 1^ miles by f, trending north and south. No lagoon. 

 Wooded. 



Margaret, Paumotu Archipelago.— 20° 42' S. 143° 4' 

 W". Diameter one mile, nearly circular. A small shallow 

 lagoon with no entrance. Northeast side alone wooded, and 

 in two patches. 



Teku or Four Crowns, Paumotu Archipelago. — 20° 28' 

 S. 143° 18' W. Diameter 1£ miles, nearly circular. A 

 small lagoon with no entrance. Southwestern reef bare ; five 

 patches of forest on the other part. 



Washington Island.— Lat. 4° 41' N. Long. 160° 15' W. 

 3 miles by li, trending east and west. It is a dense cocoanut 

 grove with luxuriant shrubbery. No lagoon. The shore 

 platform is rather narrow. A point of submerged reef, one 

 and a half miles long, stretches out from the southwest end. 

 Did not land on account of bad weather. 



Enderlury's.—Z % S. 171° 15 W. 2f miles by 1 mile 

 nearly, trending N. N. W., and S. S. E. ; form trapezoidal or 

 nearly rectangular. Little vegetation on any part, and but few 

 trees. The lagoon very shallow, and containing no growing 

 coral ; its shores of coral mud, allowing the foot to sink in 

 eight or ten inches, and covered in places with saline incrus- 

 tations. Shore platform one hundred feet or less in width, 

 and surface inclined outward at a very small angle ; covered 

 with three or four feet of water at high tide, and with few 

 corals or shells ; beyond this, falls off four to six feet, and then 

 the bottom inclines for one hundred yards or more. The beach 

 very high and regular; rises eight feet at an inclination of 



