440 Mr Gardiner, The Coral Reefs of [Mar. 7, 



sea, about 4 yards broad at the base. There is no shallow reef of 

 any sort and, although the rock at the sea level is covered with 

 nullipores, these have nowhere attained a thickness of more than a 

 few inches. The concavity, which is very shallow, is covered with 

 great masses of rock with deep fissures between, leaving a channel 

 to the cleft through which the water rushes with great force. 

 These masses can still be seen for a short distance outside the 

 mouth of the horse-shoe, but while the surface of the inner masses 

 is studded with corals, here their summits are completely covered 

 with nullipores, only a few colonies of Pocillopora, Madrepora 

 and Millepora growing on their sides. Around the island to 15 

 fathoms these masses and ridges continue, but after 25 fathoms in 

 a few yards no bottom was obtained with 50 fathoms ; the slope, 

 however, is not quite so rapid along the line of the three 

 islands. 



TJea has no reef, but, where the cliffs pass into the water, 

 nullipores grow freely and have in many places formed a platform 

 at the low-tide level, extending out for a few yards, dropping off 

 almost perpendicularly into 20 fathoms. In one position where a 

 stream has cut its way down to the sea, a broader platform has 

 been formed by these algae, which do not seem in any way affected 

 by the fresh water. 



Kiliga Point and the islands of Solkopi, Sol Onau and Afaga 

 present in places the same features as Hoflewa and Uea, but off 

 Afaga the reef broadens. At its north end there is no platform 

 of any sort ; then to the south at low-tide level a flat, smooth 

 platform succeeds, covered with nullipores. Having attained a 

 breadth of about 10 yards, it commences on its inner side to be 

 slightly hollowed out, forming a channel. The platform continues 

 to the south, retaining a constant breadth of about 9 yards but 

 with its outer edge raised about 8 inches above the low-tide level, 

 while the channel increases with the breadth of the reef, giving 

 rise to a pool with about 3 feet of water at low tide between the 

 island and the platform, in which fissures have now appeared, 

 running in for a few yards. 



Off the cliffs of Sororoa the reef is only about 25 yards broad, 

 and consists of a channel about 4 feet deep and a platform 8 yards 

 broad ; but, while the channel off Afaga is cut off from the sea, 

 it is here directly connected by a deep, broad fissure, to which a 

 strong current sets at ebb tide. Perhaps owing to this, it is 

 devoid of all coral growth and more or less covered with nullipores, 

 while the pool off Afaga has the same species of coral as were 

 found on the reef-flat elsewhere. The cliffs behind are in no way 

 undermined, being indurated with carbonate of lime and extremely 

 hard. 



Bound the most westerly point of the island the reef is similar 



