408 Proceedings of the lloycd Physical Society, 



Distribution. 



British Seas. — Between Rockall and Rona, 547 fms. (" Porcu- 

 pine" Exp., fide Agassiz, 2). 80 miles K-W. of the Butt of 

 Lewis, warm area, *' PorcujDine " (1869), St. 89, 445 fms. 

 (Thomson, 1). West coasts of Scotland and Ireland (Thomson, 2). 



Other Localities. — Coast of Spain and Portugal (''Porcupine" 

 Exp.,^(ie Agassiz, 2). Straits of Florida, 138 fms. (Agassiz, 2). 

 West Indies, 103-373 fms. (Agassiz, 5). 



6. Asthenosoma fenestratum (Wyville Thomson), Agassiz. 



1874. Calveria fenestrata, Wyv. Thomson, ''Porcupine" Echin., Phil. 



Trans., p. 741, pi. Ixiii., figs. 9, 9a; pis. 



Ixvi. and Ixvii. 

 1881. Astlienosoma fenestratum, Agassiz, "Challenger" Echin., p. 210. 



Diagnosis. 

 The overlapping portions of the jDlates are wider than in A. 

 hystrix, but the strap-shaped portions are narrower, leaving wide 

 membranous fenestras between them ; primary tubercles fewer and 

 more remote than in C. hystrix ; large pedicellarise with four 

 branches, each bearing a curiously curved disc. 



Distribution. 

 British Seas. — Off Kockall ^ (Thomson, 2). 

 Other Localities. — Coast of Portugal (Thomson, 2). Off Cape 

 Finisterre, "Porcupine" (1870), St. 10, 81 fms. (Thomson, 1). 



EcHiNOMETRiD^, Gray. 

 Test firm, regular ; tubercles imperforate ; ambulacral pores in 

 four or more pairs ; branchiae oral. 



4. Strongylocentrotus, Brandt. 



1835. Strongylocentrotus, Brandt, Prodr. descr. anim. Mertens. obs., i., 



p. 63. 



Test spheroidal, or subpentagonal depressed ; tubercles non- 

 crenulate, in primary and secondary vertical rows ; pores in 

 curves of four or five (sometimes, near the mouth, three) pairs ; 

 perignathic girdle with high ridges and a tall arch. 



7. Strongylocentrotus drbbachiensis (O. F. Miiller), Agassiz. 



1776. Echinus Drohachiensis, O. F. Miiller, Zool. Dan. Prodr., p. 235. 

 1828. ,, subangularis, Fleming, Brit. Anini., p. 479. 



^ Agassiz (5) gives the depth as 445 fms., which would correspond to St. 89 

 of the "Porcupine " cruise of 1869. 



