PALAU — BAYER AND HARRY-ROFEN 491 



Palao Tropical Biological Station were attracted by it 20 years ago 

 and made a survey of it that was reported in the first volume of their 

 journal (Abe, 1937) . We became greatly interested in that study and 

 had decided, even before reaching Palau, to resurvey the same area to 

 see what had happened to the different habitats since they were origi- 

 nally studied. This area is an island-studded lagoon, partly enclosed 

 by Koror Island (pi. 4), which the Japanese called Iwayama-wan, or 

 "Eocky -mountain Bay." The Japanese name is generally accepted 

 now, because the nearly forgotten original Palauan name for it is a 

 matter of debate (some maps use Kramer's coined name for it, "Songel 

 a Lise," which, although utilizing Palauan words, is a European inven- 

 tion). We therefore use Iwayama Bay as a neo-Palauan name. 



Iwayama Bay is a roughly circular body of water about V-/ 2 nautical 

 miles in diameter, enclosed by Koror on the north and Auluptagel on 

 the south (see map, fig. 3). Its west entrance is a long, narrow pass 

 called Lebugol Channel, and its east entrance a wider, coral- and sand- 

 choked passage called Ngasaksao Pass. The western arm of Koror 

 is volcanic land with a wide, muddy mangrove shore ; its eastern arm 

 is limestone, like Auluptagel and the 40 small islands in the Bay, with 

 a fringe of corals. The Palauan names for most of the islands are all 

 but forgotten (Sumang Y. succeeded in tracking down most of them 

 by lengthy conferences with the prominent patriarchs of Koror) so, 

 to simplify matters, the Japanese students assigned each island a 

 number, which they actually emblazoned on them in white paint. 

 These roman numerals are still legible on some of the islands, and we 

 also found that system more convenient to use than names, either 

 Palauan or Japanese. N. Abe and his colleagues further divided the 

 Bay into "divisions" bearing letter designations (see fig. 3), in most 

 of which they studied transects from island shore to reef margin. In 

 the process of collecting, we revisited each of the transects in the bay 

 and studied the 16 divisions, wherever possible taking photographs 

 of the coral growth, animal communities, and general habitat. 



Because of the many islands and narrow passes, tidal currents are 

 swift at many points in Iwayama Bay. The Islands, which are very 

 close together, rise up almost vertically from the bay floor and create 

 very narrow, deep waterways many of which are 100 feet or more in 

 depth. The islands are deeply undercut at the high-tide line (pi. 6, 

 fig. 2) — as much as 5 to 10 feet — forming deep "notches" above a sub- 

 marine shelf of variable width. In favorable localities where the cur- 

 rent is strong, as on the north shore of island 29, coral growth on the 

 shelf and vertical submarine cliff is exceptionally luxuriant. Here, 

 one could stand among flourishing corals and look either directly 

 overhead into dense jungle vegetation or straight down the coral preci- 

 pice into a hundred feet of deep blue water. Occasionally we saw the 



