MAKEMO. 105 



feet from the point where the so-called reef may be said to begin, where 

 there is from one to three feet of water at low tide. This gentle slope is full 

 of great patches of Nullipores and coralline algoe separated by lanes of coral 

 sand and of broken shells, with here and there a coral patch of greater or 

 less extent. The sea face of this reef flat is lined with a belt of great masses 

 of boulders, probably outliers of the old ledge, standing up inside of the 

 breakers at this stage of the tide (nearly low tide). It was impossible to 

 judge of their composition, as there were none accessible on the lagoon face of 

 the reef flat. 



The lagoon face of this wide reef flat was here and there edged with 

 sand bars, the beginnings of small islands and islets. Here also, as in so 

 many other atolls of the group, there were occasional bars of coral shingle 

 and smaller rolled material derived from the disintegration of the large 

 masses edging the sea face of the rim flat. A line of soundings run 

 into the lagoon showed a very gradual slope, from 8 fathoms in the 

 middle of a mass of shoals about 500 to lOOO feet from along the lagoon 

 edge of the outer reef flat, towards the deepest part of the lagoon, in about 

 21 fathoms, rather more than half-way across. From this point we strike 

 19 fathoms at a distance of six miles from the ship, and eight miles off it 

 was 15 fathoms, the depth we found off the opening where we were at 

 anchor. 



We passed not less than twenty-four shoals in a distance of not more 

 than live miles from the lagoon edge of the flats, the slopes of all of which 

 were occupied by corals extending to a depth of 16 fathoms or so into 

 the lagoon. Bars are formed here and there. Algae were also seen growing 

 on the bottom, and large Nullipore patches. There were more than thirty 

 shoals along the line of soundings we ran across the lagoon. Here and there 

 a few heads of old ledge rock showed above the water line, and where deeper 

 the tops were seen to be discolored with masses of Nullipores and patches of 

 growing corals extending along the slopes. 



With the aid of the water glass we were able to see that the bottom of 

 the lagoon was everywhere covered with patches of Nullipores and coralline 

 algae and of corals, mainly Madrepores, in all but the deepest parts of the 

 lagoon down to sixteen fathoms or so. 



