3r 



A MEMOIR 



ON 



THE ECHINODERMATA 



OF THE 



AECTIC SEA TO THE WEST OF GREENLAND, 



BY 

 P. MARTIN DUNCAN, M.B. (LOND.), F.R.S., F.G.S., F.L.S., 



HON. FELLOW KINO'S COLLEGE, LONDON, CORRESPONDENT OP THE ACADEMY OF NATURAL SCIENCES of 



PHILADELPHIA, TJ. S. ; 



AND 



W. PERCY SLADEN, F.G.S., F.L.S., &c. 





LONDON: 

 JOHN VAN VOORST, 1 PATERNOSTER ROW, E.G. 



MDCCCLXXXI. 



