460 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 117 



Hawaiian islands, Chevreux (1908) reported on amphipods of the 

 Gambler archipelago. Dana (1853) described numerous tropical 

 Pacific species, some of them still obscure because only the females 

 were described; but his work provided the groundwork for later study. 



Other important tropical studies were made in the Indian Ocean by 

 Chevreux (1901, Seychelles) and Walker (1904, Ceylon; 1905, Lac- 

 cadives and Maldives; 1909, general) and m the Ked Sea by Schellen- 

 berg (1928) and Spandl (1924). The numerous works of Haswell, 

 Chilton and Hurley in Australia and New Zealand show that little 

 relationship of those faunas is borne to the tropics, but of course the 

 northern half of Australia still has not been explored for amphipods. 

 Pirlot's excellent series of Siboga monographs (1930-38), although 

 primarily of interest for the deep sea, nevertheless contains valuable 

 information on shallow-water Indonesian and Philippine amphipods. 



Faunistic impoverishment of ATOLLS. — Atolls and small volcanic 

 islands of Micronesia are of especial interest to faunistic biologists be- 

 cause an impoverishment of many groups of organisms would be 

 expected in comparison with faunas of large islands and continents 

 in the tropics. Micronesia primarily offers an epifaunal environment 

 in the shallow sea, with scarce remnants of muddy coastal shelves 

 fringmg larger islands and continents. Hence the lack of shallow sea 

 bottoms, the dimmution of environmental variability and the decrease 

 of food from runoff should be lunitmg factors. Since most Amphi- 

 poda are either debris and detritus feeders or algal chewers they 

 especially should be restricted in diversity. Although fine calcareous 

 muds exist in lagoons of atoUs and support burrowing amphipods, 

 apparently not many dredgings or grab samples have been taken in 

 the past, for there are few ampeliscids, phoxocephalids, haustoriids, 

 and oedicerotids reported from atolls or sharply sloped islands and few 

 are expected because atoU waters are so free of the detrital food of these 

 organisms. Thus, the amphipod fauna of atolls should be composed 

 largely of those species nestlmg in epifaunal coral reefs, those chewing 

 the limited fleshy algae in these environments, and the inquilinous 

 forms that are subparasites in coelenterates, ascidians, and sponges. 

 In comparison with continents, atolls should present a repletion of 

 these hosts, especially coelenterates. 



Unfortunately, the amphipods of continents in the tropics are poorly 

 known so that comparison with islands is impossible. A great deal of 

 work remains to be done in Indonesia, the south China Sea and all the 

 continental coasts of the tropical Indian Ocean before any idea of 

 faunal diversity is realized. Many other comparisons of vital interest 

 are impossible because of the lack of knowledge in the area so outlined. 

 For instance, it is not known whether increased diversification of 

 amphipods occurs from the cold-temperate to the tropics because of 



