DESCKIPTION OF SMALL L^LANDS OF THE ATOLL. 93 



conjunction of -westerly winds and high tides, while tlic sea has invaded and divided it into two, thns 

 giving rise to a channel, through which at certain times water is flowing. 



The lagoon side, however, of Te Falaoingo nnist have remained almost stable for some years, as is 

 proved by the size of the trees, though, on the west side, clusters of the " Ngie" trees {I'cmpliU aciihihi), 

 some distance out, mark the comparatively recent boundary of the island oceanwards : this boundary has 

 now receded in places to half the width of the island at that time, l)ut without aft'ecting its lagooii 

 boundary to any considerable extent during the recent past. 



It is now, with its few cocoanut trees and shrubs, little more than the narrow remnant of what it 

 evidently has been. Probably the small sand cay to the north of it represents the shifting remains of 

 a long since detached extension of this island, which itself is now slowly approaching a state Imt little 

 superior to it. The Porifes and lireccia sheet which surround this islet and the sand cay are evidently 

 continuous under it, as the Pontes are seen in a few places appearing above the surface of the islet. 

 The lagoon platform on the east side of the islet, though rugged, is very much less so than is that 

 on the ocean side, the forces jwoducing corrosion having evidently been less violent here than on 

 that side. 



The history of Falaoingo is comparable to that of Tefala in so far as the Porife.<i blocks, breccia 

 sheet, and the shifting of its finer material lagoonwards is concerned. The former islet, however, is 

 without the fine and coarse sandstones and newer breccia formations which constitute so conspicuous a 

 feature on the latter. 



TUTANGA. 



The Poiifc--i l^locks and breccia sheet noted at Te Falaoingo are continuous to and around this islet. 

 Between the two islands are a tidal channel and a boat channel, through both of which the water often 

 runs rapidly, and the latter must be forded, even at low tide ; in each, small corals of two or three species 

 are living. The superior height and luxuriance of the vegetation on this islet makes it a conspicuous and 

 beautiful object both far and near ; though small in area, it eclipses in the above respect many of very 

 much larger extent around this S.W. corner. Its damp moss-covered blocks of coral and l)reccia, with 

 their numerous ramifying caverns, and dissolving clinker-field-like floor, are evidently well suited to 

 its flora. 



The base of this islet appears to consist of the same formation as that siirrounding it, but it differs from 

 most other islets, especially on the western rim of the atoll, in that the foundation of breccia and Pontes 

 in its centre is dissolving. These attain a height from 3 to 5 feet above high water, and between them there 

 exist deep pits with rugged sides and bottom, and of greatly varying depths, communicating with each 

 other by equally tortuous subterranean passages, in which the water rises sympathetically rather than 

 simultaneously with the tides. The whole is sheltered by towering cocoanut trees and closely veiled by 

 luxuriant tropical ferns, shrubs, creepers and thickly growing mosses; rendering clambering over and 

 through it (walking is out of the question) and the examination of its vegetation-covered subterranean 

 recesses both difTicult and hazardous. 



It is certainly a typical surface solution area of its kind, one that has its less pronounced analogues on 

 some of the islets in occasional solution areas, usually met with between the so-called clinker fields of the 

 ocean side and the sand deposits of the lagoon side, though occasionally in the midst of the former. Still 

 it is undoubtedly an area where the surface vegetation is exercising a very active and continuously 

 corroding influence which, while it abstracts nutriment from the rocks, also renders them more susceptilile 

 of the dissolving effects of the waters from above and below. The most active solution appears to be 

 limited to the central part of the islet, and as the lagoon side is approached, its intensity is gradually 

 but decidedly reduced till it appears nearly or quite to cease. The foraminiferal sand and small fragmental 

 material forming the surface of this east side (as well as on the north and south) probably obscures a 

 continuance of the Porifes area which can lie seen outside it, and which occurs so markedly in the centre of 



