536 W. DE MORGAN. 



The plane of junction between the stump and the cylindrical spine is 

 constricted, so that the spine might easily be brushed off the grain, as 

 in the case of 0. ahyssicola. There is no indication of scales on the 

 disc as in 0. ahyssicola, and the spines are equally thick on the ventral 

 and dorsal surfaces. 



Considering the immaturity of the specimens, and the variability 

 of spinulation in young ophiurids, it would be rash to finally diagnose 

 these as 0. bidentata, but their general appearance makes it probable 

 that they belong to that species. 



OPHIOCOMIDiE. 



Ophiocoma nigra, 0. F. Miiller. 

 Station VII. j-j-^ fathoms. 18 specimens. 



EOHINOIDEA. 



Cidaridae. 



Cidaris papillata (Leske), 1778. 



Station XI. 146 fathoms. 17 specimens. 

 Station XII. 246 fathoms. 14 specimens. 

 Station XIII. 412 fathoms. 19 specimens. 



ECHINOTHURIID^. 



Phormosoma luculentum, Agassiz. 



Station XII. 246 fathoms. 1 specimen. 

 Station XIII. 412 fathoms, 3 specimens. 



This species is described and figured by A. Agassiz in his report on 

 the Echinoidea. The voyage of H.M.S. Challenger, Vol. Ill, p. 97, 

 Pis. IX, X, Xa, Figs. 8-7; PI. XXXIX, Fig. 8; PL XL, Figs. 

 31-36 ; PL XLIV, Figs. 25-27. 



It was obtained by the Caudan Expedition (6a), and in the 

 N. Atlantic by the Hirondellc. 



ECHINID^. 



Echinus norvegicus, Dub. o. Kor, 1844. 



Station V. 109 fathoms. 1 specimen. 



Station VII. ^j fathoms. 1 specimen. 

 Station XII. 246 fathoms. 3 specimens. 



These are young animals. The measurements of the largest taken 

 at Station XII are: Diameter of test, 13-5 mm.; height of test, 

 7"5 mm. ; length of longest spine, 13 mm. 



