ALEXANDER AGASSIZ MAYER. 461 



period of elevation, as in the Fiji Islands, or by dissolving away of 

 the inner parts of an elevated limestone island, as at Bermuda, or 

 Fulangia in Fiji, or we may have a submerged crater the volcanic rim 

 of which may erode away to beneath sea level, thus giving a founda- 

 tion for a ring-shaped coral reef. 



Unfortunately the very multitude of Alexander Agassiz's observa- 

 tions and the somewhat confused style of his writing renders him 

 difficult to follow. Had he enjoyed greater experience as a lecturer 

 he might have become a clearer writer, for he constantly assumed that 

 his readers were as familiar with the subject as hmiself, and that a 

 few words would make his meaning as clear to them as to him. 



It is to be regTetted that of the three great writers upon coral reefs 

 Darwin saw only one atoll, Dana sailed past many, but was per- 

 mitted to land upon few, for the islands were then inhabited by 

 dangerous cannibals, and Agassiz was compelled to cover such a 

 vast field that certain of his conclusions, as he states himself, are 

 still tentative; for the solution of some of the questions presented by 

 these problems demands a more intensive and prolonged study than 

 he was able to devote to them. 



\Vliile in the Hawaiian Islands in 1885 he found that the coral 

 reefs have repeatedly been buried under lava floes, and that the corals 

 have again grown over the submerged lava. The reefs have nowhere 

 been elevated more than 25 feet above sea level, but the coral sands 

 and shell fragments have been blown upward along the mountain 

 slopes and have formed limestone dunes, which the rains have ce- 

 mented into solid rock. These wind-blown limestone ledges may be 

 found TOO feet or more above the level of the sea. 



In 1890 he published a paper showing that reef corals may become 

 2| inches thick in less than seven years, his observations being based 

 upon a study of corals that had grown upon the Habana-Key West 

 cable. 



In 1887 Alexander Agassiz was invited by the United States Fish 

 Commission to assume the scientific direction of an expedition of the 

 steamship Albatross between Panama and the Galapagos Islands, but 

 he was unable to accept until 1891, when, from February until May, 

 he cruised with the Albatross from Panama to Point Mola, thence to 

 Cocos, Malpelo, and Galapagos Islands, and from Acapulco to the 

 Gulf of California, making 84 deep-sea trawl hauls, soundings, and 

 temperature observations, and in five m.ore stations using the sur- 

 face and submarine nets. 



A significant feature of this expedition was due to the invention 

 by Lieut. Commander Z. L. Tanner, United States Navy, of a self- 

 closing net, which enabled one to obtain marine animals at any 

 stratum of depth, and thus to determine the range in depth of marine 

 creatures. The use of this excellent net led Alexander Agassiz to con- 



