26 THE VOYAGE OF H.M.S. CHALLENGER. 



this last species I offer the suggestion with much doubt, for the description given is alto- 

 gether inadequate for classificatory purposes. I am unable to recognise any of these forms 

 amongst the Challenger material. 



Of the several new species from the North-American coast described by Verrill during 

 the last few years under the generic name of Archaster, none appear to belong to the 

 senus Pontaster. I would, however, sucwest that the Asterid from this region which 

 has been referred to Archaster tenuispinus may perhaps be found to be the same as the 

 form I have named Pontaster liebitus. 



Cliorology of the Genus Pontaster. 

 a. Geographical distribution : — 



Atlantic : Six species between the parallels of 80° N. and 40° S. 



Pontaster for cipatus and Pontaster hebitus, off the coast of North 

 America. Pontaster limbatus in the Faeroe Channel, off the west coast 

 of Ireland and S.W. of the Scilly Islands. Pontaster tenuispinus in 

 the Faeroe Channel, off the Scandinavian coasts, and as far north as 

 Spitzbergen. (Also Greenland^cfe Liitken, and North America fide 

 Verrill. ) Pontaster tenuispinus, var. platynota, in the Faeroe Channel 

 and off the west coast of Ireland. Pontaster venustus, east of the 

 Azores, and Pontaster venustus, var. robusta, off the Cape Verde Islands. 

 Pontaster pristinus, off the eastern coast of South America. 



Pacific : Four species between the parallels of 40° N. and 50° S. 



Pontaster oxyacantkns, south of Japan. Pontaster trullipes, west 

 of the island of Luzon (Philippines). Pontaster subtuberculatus, east 

 of Australia. Pontaster planeta, west of South America, near the 

 entrance to the Straits of Magellan. 



Eastern Archipelago : Two species between the parallels of 0° and 10° S. 



Pontaster mimicus in the Arafura Sea. Pontaster teres, in the 

 Banda Sea, between the Ki Islands and Banda Islands. 



Southern Ocean: One species between the parallels of 40° and 50° S. 



Pontaster forcipatus, var. echinata, between Marion Island and the 

 Crozet Islands. 



/3. Bathymttrical range: 70 fathoms to 2650 fathoms. 



Six species are found above the Abyssal zone (i.e., in depths less than 500 

 fathoms), viz., Pontaster hebitus, Pontaster limbatus, Pontaster oxyacanthus, 

 Pontaster planeta, Pontaster tenuispinus, with its var. platynota, and Pontaster 



