The Voyage of H.M.S“Challenger” 
F.H.Michael del et lth 
1-2, BATHYBIASTER LORIPES .n sp. 3-4. PSEUDARCHASTER DISCUS,n sp 
5-6. PSEUDARCHASTER INTERMEDIUS,n.sp. 7-8. PSILASTER ACUMINATUS,n sp. 
2-11. PSILASTER GRACILIS,n sp. 
Mintern Bros.imt 
