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During the period February 13 to 20, 1973, a visit was made to Canton Island for the purpose of conducting a preliminary survey of marine turtle nesting populations. Although previous investigators have described the sea birds (Buddle, 1938; Murphy G., 1954), insects (Van Zwaluwenburg, 1943, 1955), and vegetation (Hatheway, 1955), very little is known about the marine environment of Canton or the other seven atolls (Enderbury, Birnie, Phoenix, Sydney, Hull, Gardner and McKean) which comprise the Phoenix group. Publications dealing with marine life are limited to a description of fishes collected during the 1939 Bushnell Expedition at Canton, Hull, Enderbury and McKean (Schultz, 1943) and to an identification of some marine algae at Canton Island (Degener and Gillaspy, 1955 Dawson, 1959).

In a typical High Island coral reef complex of French Polynesia (transect of Tiahura, Hoorea Island, Society Archipelago!, 73 species of decapod Reptantia and stomatopod crustaceans were collected. Over 9 stations localised along the transect, 3 different units of hard coral substrate of simi1ar volume (about 17 litres each), were sampled at each station. The results are discussed from two aspects : the first shows that at least 50 carcinologic species occur within the cavitary biotopes ; 16 species (mainly Xanthid crabs), represent more than 90% of all collected individuals. Most of the dominant species are widely distributed along the transect (Chlorodiella barbata, Pilodius pugil, Lipcarpilodes integerrimus, Galathea aculeata), and locally, some others are numerically important (Chlorodiella Laevissima, Globopilumnus globosus, Daira perlata,Phymodius ungulatus, etc.). The second aspect concerns the repartition of species in the different biotopes in relation to their feeding habits. Based on the functional morphology of chelipeds, mouth-parts and gastric sill, and on gut content analysis, the species were placed into 5 MORPHO- LOGIC GROUPS : filter-suspension feeders, omnivores/herbivores, omnivores/carnivores, generalised omnivores and predators. The feeding habits and the distribution pattern of abundant species suggest that trophic and habitat partitioning say exist. The predominant species show either different nutritional modes, or inhabit different areas and/or biotopes. Distribution patterns of the morphologic groups ip the different substrates are proposed, and schemes of interspecific relation; are analysed.

Jonathan Sauer (1961) remarked, in his Coastal Plant Geography of Mauritius, that the chance to study the coastal vegetation there was like being "admitted to a field worker's paradise" and stressed that "most tropical coasts are beautiful and exciting, particularly to people concerned with natural processes . . .." The same can certainly be said for the tropical coasts of the often Edenized islands of the Pacific Ocean. Their "beauty and excitement" is considerably enhanced, however, when one is also "concerned" with cultural processes and ethnobotany, in particular, the immense cultural utility of coastal plants, a factor which strongly influences the distribution and character of plant communities.

Nukutipipi atoll (5 km2), of volcanic origin 16-17 million years old on the Pitcairn (hot spot) Hereheretue line, presents a land flora and fauna of low diversity but with a Pisonia forest and hundreds of resident red-tailed tropic birds. Nukutipipi suffered from the 1983 hurricanes : destruction of vegetation and motu as well as sand lagoon mollusc populations. The north and south rims present original geomorphological structures. Lagoon without patch reefs reaching the surface is characterised by dome patch reefs all constituted of dead Acropora with few scleractinian and mollusc species, but an important algae coverage. All these characteristics indicate the precariousness on a time scale of such a so tiny atoll, land and marine, with a closed lagoon.

This paper describes the channels known as hoa which are characteristic of atoll land rims and of some islands on barrier reefs, where they often dissect previously more continuous reef-top sediment accumulations and conglomerate platforms. They are especially common in the central Pacific, and are particularly well developed in some atolls of the Tuamotu Archipelago and on some of the Society Islands. Published hypotheses accounting for the origin and development of hoa of different kinds are outlined. Contemporary hoa on the north side of Hull Atoll in the Phoenix Islands are described and surveyed, as are older, probably Holocene hoa, here termed 'paleohoa', on the same atoll. Regional and local distributions of hoa and paleohoa and differences in hoa morphology are used to assess theories of hoa formation. Both hoa and paleohoa are attributed to hurricane activity, and the presence of paleohoa may thus give an indication of the distribution of hurricanes in the Holocene.

The shorefishes of Ouvea, an isolated atoll in the Loyalty Islands group of New Caledonia, had not been surveyed prior to 1990. An extensive survey was conducted by ORSTOM between 1991 and 1992 to obtain baseline information on the shorefishes. A total of 653 taxa among 72 families are now documented from this area. The most diverse families are the Labridae (69 species), Pomacentridae (58 species), Gobiidae (54 spccies),Serranidae (39 species), Chaetodontidae (31 species) and Apogonidae (28 species). The absence or very low diversity of some families (Clupeidae, Nemipteridae, Siganidae) or genera (Abudefduf, Neopomacentrus) is similar to findings for other isolated islands of the Coral Sea. Of the 653 species recorded from Ouvea, 51 species have not been reported from New Caledonia, a large high island to the South. Only one endemic species, Luzonichthys williamsi, has been recognized among the shorefishes at Ouvea. A number of Pacific Plate endemic species were recorded at Ouvea. which is positioned on the Australasian Plate to the south of the edge of the Pacific Plate. Antennarius duescus, previously known from three specimens taken at the Hawaiian Islands, is recorded from a single specimen taken at Ouvea. Another antitropical distribution pattern is exhibited by Dinemalichthys riukiuensis, which is known to occur at Fiji, Ouvea and Queensland in the South and from Okinawa.