Boone, Echinoderynata, Cruises of "Ara" and "Alva" 173 



Order: EXOCYCLOIDA 



Suborder: Spatangina 



Family: HEMIASTERIDAE 



Genus: BRISASTER Gray 

 Brisaster moseleyi (A. Agassiz) 



i 



Plates 65, 66 and 67 



Type : The type series of this characteristic Chilean species 

 was dredged by H. M. S. "Challenger" at stations 146, 305, 307, 

 309, 310, also off London River, Christmas Harbor, and Kergue- 

 len, in depths ranging from 110 to 245 fathoms. Those thirty 

 specimens collected on the west coast of Chile, at station 305, in 

 120 fathoms, station 309, 40 to 140 fathoms, station 310, 400 

 fathoms, and station 311, 245 fathoms, all mud bottom, are in the 

 British Museum of Natural History; the remainder are in the 

 Museum of Comparative Zoology, Cambridge, Massachusetts, and 

 one of these, the specimen from off London River, Kerguelen, 

 depth 110 fathoms, has since been made the type of a distinct 

 species, Brisaster herguelenensis H. L. Clark, seven more speci- 

 mens of which, from the same locality, are in the British Museum 

 {vide Clark, 1925). 



Distribution: In addition to the "Challenger" records for 

 this species, Brisaster moseleyi A. Agassiz, it has since been taken 

 by the United States Bureau of Fisheries Steamer "Albatross" 

 at seven stations off southern Chile : in the western entrance of 

 the Strait of Magellan, off Queen Adelaide Island, near Cambridge 

 Island, off Campana Island, Taytao Archipelago, and near Valdi- 

 via in a bathymetrical range of 61 to 677 fathoms. The "Alva" 

 station in Reloncavi Inlet, Bahia de Cochamo, Chile, adds another 

 locality for this interesting Echinoid. 



Material examined : Seven specimens, dredged in Reloncavi 

 Inlet, Bahia de Cochamo, Chile, depth 7 fathoms, February 16, 

 1935. 



Technical description : Horizontal long diameter 61 milli- 

 meters, width diameter where greatest about at the center, 55 

 millimeters ; vertical diameter where highest about at the apex of 

 the abactinal system, 37 millimeters. Abactinal system 41 milli- 



