25 Emery et al. state (p. 57): The Tagoons cen be considered as made up chiefly of two distinct but superimposed environments: (1) the topographic highs, characterized by active growth chiefly of coral with relatively Jittle accumulation of granular material ,and (2) the gentle slopes or flat areas between coral knolls where granular debris from the reefs, from the water above, and from Halimeda and Foraminifera growing on the bottom are deposited. Minor amounts of coral are found in the flat area, as talus debris near the base of the coral knolis and as growth in situ on the bottom. The coral knolls which dot the lagoon often reach gigantic proportions-- rising to within several fathoms of the lagoon surface. Wells (1954) totaled C= genera and 266 species of coral from the Marshall Islands and describes treir species distribution in the atoll by zones bases on habit preferences ‘cr wincward or leeward, lagoon or seaward, depth, and temperature. y Emery et . (cp. cit., p. €2) estimate that 5 to 20% of Bikini Lagoon is covered by “°r2* growth, Foth Anikouchine (1961) and Emery show that generally well-defined phyee yd anc aeodraphical parameters coincide with the distribution of unconsoli- tee sedimentary materials in Bikini and Rongelap Atoll lagoons. Foramini- "rr ae" fine “coral” debris (comminuted coral, Halimeda,shells) comprise the “Sa sncant component of beach materials. ‘ The foraminifera Calcarina . nee "_fti and Marginopora sp. account for between 25% and 50% of the local “ce Of beach sands (Emery et al., op. cit. p. 58). In general, these '» © foraminifera decrease in abundance with increasing depth to abund- | ¢ Tess than 10% at around 26 meters. Munk and Sargent (op. cit.) " "ste" teat waves dissipate 500,000 horsepower against the windward reef at <reletal and clastic reef material eroded by this frictional force 3 cymes ‘reg the lagoon, especially during high seas, and account for the