FRYER— FORMATION OF ALDABRA, ETC. 403 



like a continuous well-grown hedge about 15 feet in height. The trees have a short thick 

 trunk, long slender branches, and are very uniform in size, so that it is impossible to climb 

 a tree and obtain any view of the surrounding country. This type of bush is found where- 

 ever the jagged pointed rock occurs, and as the latter from its curious appearance is 

 known * as " champignon," the country is always referred to as " champignon country." 



Throughout the northern section the Pemjihis jungle continues and the monotony is 

 only broken by the frequent occurrence of curious natural pits in the rock ; up to within a 

 quarter of a mile of the sea they are partially choked with guano but after this are usually 

 found to contain salt water, which fluctuates tidally, thus showing that the land-rim can 

 be more or less completely traversed by sea-water. Naturally the water dissolves the 

 rock away, and thus the sides of the pits overhang and break down, and the pits are 

 always increasing in size. 



After a mile of " champignon," creeks from the lagoon were met with and soon after 

 the mangrove swamp was reached. At the junction of land and swamp are low cliffs 

 3 or 4 feet high which show the effects of erosion in that they are much overhanging, 

 while small islands and large rocks are continually being cut off from the mainland. After 

 a time the latter take on the mushroom shape typical of erosion ; then, the " stalk " of the 

 mushroom breaking down, the rock or island tumbles over and is itself gradually eroded 

 away. 



The mangrove swamp measured a quarter of a mile in breadth in the section. It is 

 very flourishing, the trees standing in thick white mud, which may be very shallow 

 or may have a thickness of many feet before rock is reached. The trees usually grow 

 in this mud, but may also be found in numbers on the sides of the rocks and islands, and 

 along the lagoon cliffs : their roots then pass down through holes and cracks in the 

 overhanging portions of the rock to the mud underneath and by increasing in size form 

 powerful instruments for breaking off large masses of rock. At high tide the swamp fills 

 with water, which churns up the white mud and then, as it descends, sweeps it away into 

 the lagoon and the finer particles out to sea, though the larger particles remain as sand in 

 the lagoon until sufficiently triturated and reduced by sand-living animals to be carried 

 away also. The loss in this manner must be very large and, as there is no evidence 

 that the total quantity of mud is decreasing, it appears that rock disintegration must 

 be speedy enough to counterbalance such loss, a subject which must be referred to again 

 later. 



The typical section for the south-east of the land-mm. The second section passes from 

 the lagoon near a creek known as Abbot's creek past the wells of Takamaka (see Chart) 

 to the south coast. Beginning again at the sea it is at once noticeable that the cliffs, 

 though formed of the same rock as was noted in the cliffs of the northern section, are not 

 so overhanging and are marked by projecting buttresses, indicative of a slower rate of 

 erosion. Descending to the reef to find a reason for this, the quantity of sand was 

 immediately remarked, and it appears that this sand forms a partial protection against 

 the waves, even though the latter are particularly powerful on this, the windward side 

 of the atoll. 



* The language usually spoken is Creole, a debased and often hardly recognisable French jmtois. 



