III. DISTRIBUTION. 



If the fauna of the Pacific so far as it relates to the Eryhdae is compared with 

 that of other regions, it is seen that its single genus Erylus occurs in both. 

 Some of the Pacific species are similar to species found outside the Pacific, but 

 not a single one appears to be really identical with any ultra-Pacific one. 



Eight of the twenty-two known species, that is 36 %, occur in the Pacific. 



The range of the Pacific species is, so far as at present known, not great. 

 With the exception of Erylus rotundus and E. sollasii, which have been obtained 

 at various points on the coasts of the Hawaiian Islands, all the Pacific species 

 arc recorded from one locality only. 



The majority of species, the Pacific as well as those of other regions, are 

 tropical or subtropical. It is remarkable that no specimen of Erylus has hitherto 

 been found on the west coast of the American continent. 



The horizontal distribution of the Pacific species is: — 



Eastern Pacific Iskindfi. 



Erylus oxyaster. 



Galapagos. 



Central Pacific Islands'. 



Erylus monticularis, 

 " sollasii. 

 " rotundus. 



Funafuti. 

 Hawaiian Islands. 



caliculatus. 



southeastern Asiatic Islands. 



Erylus decumbens. 

 " nobilis. 



Java. 

 Ternate. 



Northeastern Asiatic Islands. 



Erylus placenta. 



Japan. 



All the Pacific species have been found in rather shallow water. 



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