OPIIIOTIIRIX MAGNIFICA. 



159 



LIST OF SPECIMENS. 



riiUil.i!;ue 

 Nuiubt-r. 



144 

 145 



146 



991 

 1112 



Original Number 

 Number. I uf Spec. 



64 

 991 



Locality. 



When 

 Collected. 



VTlience obtained. 



Museum of Comparative Zoology. 



St. Thoina.^ W. I. 

 West Indies. 



Cartliagena, New Gre- 

 nada. 



Nature of 

 Specimen. 



Smithson ian Institution. 



Carthagena, New Gre- 

 nada. 

 St. Thomas, W. I. 



A. II. Rii.se. 

 University Museum, 

 Copenhagen. 



A. Schott. 



A. Scliott. 

 A. II. lliise. 



Alcoholic. 



Alcoholic. 



Ophiothrix magnifica Lymax. 



OjMothrix mrif/nijica Lymax. Proceed. Boston Soc. Nat. Illst., VII. p. 254. 1860. 



Special Marks. — A large species ; back of disk closely spinecl ; arm- 

 spines stout, round, somewhat tapering ; color bluish. 



DescrijMon of a Specimen. — Diameter of disk, 12. 5"""' ; from outer 

 side of mouth-shield to outer corner of opposite mouth-slit, 5.G°""'; width 

 of anil without spines, 2.7'""''; length of arm, 70°"°- ; distance from outer 

 side of mouth-shield to inner points of tooth-papillj^, to that between 

 outer corners of mouth-slits, 2.4 : 2.4. Tooth-papillae aljout thirty-six, 

 arranged in two rows of about ten each, which diverge from above 

 downward, and are filled in between by smaller papilla? ; the papillae 

 grow shorter and smaller from above downward. Teeth six, squarish, 

 moderately stout, with rounded cutting edge ; uppermost one thin, and 

 so tapering as almost to be sharp. Mouth-shields small, almost circular; 

 length to breadth, 1 : 1.2. vSide mouth-shields meeting within. Under 

 arm-plates covered with thick skin, and closety joined, so that their 

 outline is indistinct ; in form irregular oval ; outer side longer than 

 inner, and slightly re-entering ; lateral sides well rounded ; length to 

 breadth, .7 : 1.3. Upper arm-plates small, with a strong median ridge ; 

 diamond-shaped, with outer angle much rounded, lateral angles sharp, 

 and inner angle very slightly truncated ; length to breadth (thirteenth 

 plate), .7 : 1.2. Brachial and interbrachial rays of disk closely beset 

 with round, stout, tapering spines, of very even length ; they are cov- 

 ered with minute thorns, and terminate in a rather blunt crown of 

 them ; these spines have usually a length of about 1.3""°-. Radial 



