422 Proceedings of the Royal Pliysical Societif. 



20. Schizaster fragilis (Diiben k Koren), L. Agassiz. 



1844. Brissus jragilis, Diiben & Koren, Skaud. Echin., p. 280, 



pi. X., figs. 47-49. 

 1847. Schizaster fragilis, L. Agassiz, Catal. raisonne, Ann. Sci. Nat., 



(3) viii., p. 22. 

 1872. ,, ,, Agassiz, liev. Echin., pp. 157, 363, 612, 



pi. xxi., fig. 3 ; pi. xxvi., fig. 42. 

 1874. ,, ,, Loven, ]Etudes, pi. xii., fig. 102 (apex) ; 



pi. xxxi. (test). 

 1874. Tripjlus fragilis, Wyville Thomson, "Porcupine" Echin., 



Phil. Trans., p. 750. 

 1883. Schizaster fragilis, Loven, Pourtalesia, pi. x., fig. 100 (pedicel). 

 1883. ,, ,, Agassiz, "Blake" Echini, Mem. Mus. Comp. 



Zool., X., p. 74, pi. xxviii., figs. 8-14. 



Diagnosis. 

 Test cordate oval, keeled behind, depressed in front, highest 

 point far back ; groove, deep and long ; mouth near margin ; 

 antero-lateral petals three times as long as posterior ; pairs of 

 pores in the anterior ambulacrum thirty-three, in the lateral 

 thirty-five, in the posterior fifteen. 



Distribution. 



British Seas. — N. and W. of Shetland, 400-500 fms. (Thomson, 



2). 



Other Localities. — Off Godthaab, 410 fms., "Valorous" Exp. 



(Norman, 4). Off Halifax, Nova Scotia, " Challenger," St. 49, 



83 fms. Off the Cape of Good Hope, St. 142, 150 fms. (Agassiz, 



3). Norway, 30-150 fms. (Sars ; M'Andrew and Barrett; 



Copenhagen Mus.). Gulf of St Lawrence (Whiteaves). Straits 



of Florida (Pourtales, fide Agassiz, 2). U. S. Coast, 37-321 



fms. (Verrill). New England Coast, 71-362 fms., "quite a 



common species near the 100-fathom line" (Agassiz, 5). 



11. Brissopsis, Agassiz. 



1840. Brissopsis, Agassiz, Cat. Syst. Ecty., p. 16. 



Test thin, more or less ovoid ; highest point nearly central ; 

 ambulacral petals unequal ; anus terminal ; subanal fasciole 

 subterminal and complete; dorsal impression complete and sur- 

 rounding the ambulacral petals. 



21. Brissopsis lyrifera (Forbes), L. Agassiz. 



1841. Brissus lyrifer, Forbes, Brit. Starf. , p. 187, cut. 



1844. „ ,, Diiben & Koren, Skand. Echin., x». 280, pi. x., 



fig. 46. 



