REPORT ON THE HEXACTINELLIDA. 



427 



Table II. — continued. 



A glance at the map shows that there were four princij)al regions from which the 

 considerable collection of Hexactinellida gathered before the Challenger Expedition had 

 been obtained, viz.: — 



1. West of Europe from the Shetland Islands to the Straits of Gibraltar. 



2. Near the West India Islands, from Florida to Trinidad. 



3. Near Japan, and especially in the Bays of Tokio and Sagami. 



4. Near the Philippines, especially off the island of Zebu. 



Besides these there are a few isolated localities in the North Sea and the Mediterranean, 

 off the Cape Verde Islands, the Seychelles, Isle de Bourbon, Malacca, Moluccas, and in 

 the Aiitai'ctic Ocean. 



From these results it is oljviously impossible to gain anything but an approximately 

 plausible conception of the true distribution of the HexactineUida. At the outset the 

 fact has to be noted, that only in the four localities specially noted as the origin of the 

 majority of the known forms and individvials, was the sea-bed satisfactorily examined 

 below a depth of 100 fathoms. This was done on the Western European coasts by the 

 dredgiugs of English and French expeditions, off the West India Islands by the explora- 

 tions of Agassiz and Count Pourtales, off the Philippines by the enterprising and 

 successful activities of the fisher folk, and off Japan by a few naturalists and especially 

 by Dr. Doderlein. 



It is of course impossible to decide whether other localities noted in the Mediter- 

 ranean, Indian Ocean, &c., represent the occurrence of Hexactinellida in altogether 

 sporadic distribution, or the existence of a richly developed and perhaps widely distributed 

 fauna, of which a few localities have been by chance discovered. 



In regard to the distribution of the several suborders and families it is impossible 

 for the same reason to glean many certain results. It is, however, worth noting in this 

 connection that none of the localities are tenanted exclusively by any one family, but 

 that aU include representatives of different groups of the system. 



