402 FUNAFUTI: THE STORY OF A CORAL ATOLL. 



safety. Such is the violence of the breakers that the tidal platform 

 presents the appearance of an almost lifeless desert; a few green and 

 brown seaweeds, little fish darting in the pools, occasional sea snails 

 with dense shells, and a few hermit crabs heavily armored, are all that 

 is seen at first glance. All the inhabitants of the tidal platform seem 

 to stand in dread of the sea; even the active shore crabs (G-rapsus) are 

 afraid of it, and only venture in when inspired by their greater terror 

 of the human form ; even then they cling tenaciously with their many 

 legs close to the sides of the rocky shore, and sidle off to laud directly 

 they fancy the enemy's back is turned. 



The observer who trusted to first impressions, and judged the plat- 

 form by its outer aspect, would fall into grievous error; it is by no 

 means so dead as it seems. On breaking off a fragment with a hammer 

 a new world of life is revealed; the rock is tunneled through and 

 through, as closely as it can be mined, by a variety of animals, which 

 have taken to an underground life as a protection against the sea; 

 worms, shellfish, crabs, sea squirts, and barnacles are to be found in 

 these subterranean dwellings; they constitute a specialized fauna of 

 marine troglodytes, which might, if we wished to add to the burden of 

 nomenclature, be designated the " Cryptone." 



After this brief description of the superficial features of the atoll we 

 may next endeavor to trace the history of that part of it which rises 

 above the sea and properly constitutes the land. The sheet of hard 

 coral rock which we mentioned as cropping out beneath the storm 

 beach can be traced into the interior of the island, where it forms the 

 floor of the central depression; and again to the lagoon side, where it 

 emerges to form the floor of the lagoon and in many places the beach 

 or as well even a low line of cliffs. In the little islet of Pava, north of 

 Funafuti, it is seen to extend continuously from one side of the land to 

 the other — from the ocean to the lagoon. 



We may, therefore, fairly conclude that this sheet of rock forms the 

 solid base on which the land above it rests. It is composed mainly of 

 slabs of coral, lying not quite horizontally, but overlapping like the 

 tiles of a roof, with a slight inclination toward the ocean side of 

 the reef. 



These fragments have evidently been derived from the outer zone of 

 growing coral. Before the land as it now exists was formed the waves 

 were incessantly engaged in tearing off fragments from the coral zone 

 and driving them across the reef into the lagoon till a thick sheet of 

 debris was the result. This became consolidated as it formed, partly 

 by the growth of incrusting calcareous alga?, and now forms the solid 

 floor of the island. 



Masses of broken corals, torn up and driven inland by the breakers, 

 continued to accumulate after the formation of the floor; and thus that 

 great pile of coral clinkers which forms the storm beach has been and 

 is still being built up. 



