THE ANIMAL LIFP: OF THE OROUP. 477 



The coral reefs of the Pacific have been miicli sludieil l)y oceanof^raphers, 

 zoolo<iists and geologists who have sought to wrest from them something of the 

 history of the formation of the islands in this vast ocean. 'IMic geologic sig- 

 nificance of the Hawaiian reefs has been pointed out in finotlicr iMjnnectioii. 



While ])ut few have ever attempted to list the various species of corals 

 found here, their study was first undertaken sei'iously long ago. In 1840-41 

 the renowned geologist James D. Dana, whose epoch-making hook on the coral 

 islands is a scientific classic, visited Hawaii and examined the i-cefs, as a 

 member of the scientific staff of the linited States Ex|)h)i'iug Expedition. As 

 a result a dozen of the more common shallow-water forms were dcscfihcd as 

 new by him in a portion of the report of that expedition, ])ul)lished in 1S46. 

 Since then others have added to tlie list, but it remained foe my ffiend. \)v. 

 T. W. Vaughan, to give the subject the attention it deserves. As a result of his 

 labors, based primarily on the collections secured by the All)atross expediti m 

 in 11)02, hut supplemented by a large collection of shallow-water coral secured 

 by mendjers of the staff of the Bisho]> Museum, we now have availabh^ for 

 the specialist a handsome monograph in which representatives of fifteen fami- 

 lies, including thirty-four genera, to which, according to that author, are re- 

 ferred one hundred and twenty-three species, varieties and forms. Of that 

 mnnber more than three-fifths are described and figured fdc the lirst time. 

 Some idea of the richness of the coral fauna of any given locality can be 

 gathei'ed from the fact that the reef and shadow waters along the soutli side 

 of Oahu, but especially at Waikiki. yielded examples of thirty-four of the 

 species enumerated. 



While a single species -'^ of mushroom-like coral was bi-ouglit to tlie sur- 

 face by the dredges of the Albatross from the great depth of eleven hundred 

 and fifty fathoms, the great majority of the forms, seventy-seven in number, 

 occur in water from one to twenty-five fathoms in dejith. Of the t'ourteen 

 genera that occur in this shallow water zone throughout the group, ten wei'e 

 collected on reefs of Oahu from Pearl llai'bor to Diamond Head. Repi-eseii- 

 tative specimens of the common genera from this locality ai-e here ligui-ed. 

 The figures will aid in the generic determination of sueli fdi-ms as are most 

 liable to be collected, but definite identification of tlie species and the almost 

 numberless forms of certain species is in nuiny cases almost imjjossihje. even 

 when the type specinu'us can be seen. 



The genera occurring in the shallow water about Oahu ma.\- I)e n^uarded 

 as the living representatives of the reef-bnildinu foi'ms that for thousands 

 perhaps millions of years have been buihliiiL;- the lime i'0(d\ that tViuLics the 

 islands. 



Of the several genera I'orihs. tlie pohaku puna o\' the nati\'es is the most 

 abundant and is representcMl by the largest inunbei- of i'm-nis. The Pocilloponi are 

 perhaps next both in size and al)undance, and like the precedinu: uenns. they 

 ranue through an extensive list of varied r(U-ms. Mimt ipura is next in abuu- 



-•'' BiithiKirtcs liairniii'tiKis. 



