A SURVEY OF THE HAWAIIAN CORAL REEFS 



YAUGHAN MacCA UGHE Y 

 Professor of Botany, College of Hawaii, Honolulu, Hawaii 



During a residence of nearly ten years in the Hawaiian 

 Archipelago the writer has had opportunity of visiting 

 and exploring many of the coral reefs, and has been much 

 interested in their formation, flora, and fauna. The pres- 

 ent paper aims to present the salient and significant facts 

 relating to the natural history of these remarkable reefs, 

 in compact and largely non-technical form. There is a 

 large scattered literature (inaccessible to the average 

 reader), dealing with the coral reefs and their life, but 

 the writer believes this to be the first time that the follow- 

 ing data have appeared within the confines of a single 

 paper. 



The Hawaiian Archipelago is situated in the midst of 

 the North Pacific Ocean. It lies between latitudes 18° 

 54' and 22 14' and 154 : 48' and 160° 13' West Longitude, 

 being about 2,020 miles southwest of San Francisco. Its 

 east and west extension is nearly two thousand miles, 

 the islands are but the apices of a titanic mountain range 

 that rises to heights of from three to five miles from the 

 floor of the ocean. 



This long archipelago, comprising about twenty-two 

 islands, is remarkable for the simplicity of its geologic 

 formations. Only two classes of rock material are known 

 in the entire group— lava and coral. There are numerous 

 subdivisions of these groups (for example, there are many 

 varieties of lava), but all the known rock-formations give 

 conclusive evidence of having originated from either one 

 of two sources— volcanic or coralline. It is extremely 

 interesting to consider that all of these islands are com- 

 pounded of two such diverse elements — one from a roar- 

 ing lake of incandescent lava ; the other from the age-long 

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