﻿OPHIOCOMA ECIIINATA. 



81 



OpMocoma nigra Mull. & Tuosch. 



Asterias nigra O. F. Mull. Zodl. Dan., PI. XCm. 



OpMocoma granulata Fokbes (non Linck.). Brit. Starfishes, p. 50. 



Ophiocoma niyra Mull. & Troscii. System der Asteriden, p. 100. 



LIST OF SPECIMENS. 



Whence obtained. 



3fuseum of Comparative Zoology. 



Gi-eenland. 

 Norway. 



Prof. Sars, 1852. 

 University Museum, 

 Copenhagen. 



Ophiocoma echinata Agass. (Fig. 5.) 



Ophiura echinata Lamk. Hist. An. sans Verteb., 11. p. 540. 1816. 



Ophiocoma echinata Agass. Prodrome. Mem. Soc. Scien. Nat. de Neuchatel, I. 1835. 



Ophiura crassispina Say. Journ. Phil. Acad., V. p. 147. 1825. 



Ophiocoma crassLipina MiJLL. & Trosch. Syst. Asterid., p. 103. 



Ophiocoma serpentaria Mull. & Trosch. Syst. Asterid., p. 98. 



Ophiocoma crasshpina Lutken. Addit. ad Hist. Oph., p. 142. 



Sj^ecial Harks. — Upper arm-spine much thickened 

 nearly square, with rounded corners. 



mouth-shields 



Description of a Sjiecimen. — Diameter of disk, 23.6°"°- ; from 

 outer edge of mouth-shield to outer corner of opposite mouth-slit, 

 g^mm. . greatest width of arm without spines, 4"°'- ; length of arm, 

 100°"° ; distance from outer edge of mouth-shield to points of tooth- 

 papilla?, to that between outer corners of the mouth-slits ^.^ ^ 

 as 2 : 2.6. On each side of the mouth-frames four mouth- 

 papilliB, of which the three outer ones have their grinding 

 edge bevelled, which makes the outer edge shorter than 

 the inner one ; the innermost papilla points towards the 

 centre of the mouth, and is stout and more conical than 

 the others ; the other three are also stout, but are more 

 flattened ; their corners and edges are rounded. On the 

 jaw, four irregular, horizontal rows of stout, rounded, close- 

 set tooth-papillEe, three in each row ; the lowest row is on a level with 

 the line of the mouth-papillae, and the tooth-papilla? of this row are 

 smaller than the rest, and moreover may vary in number, being some- 



Ophiocoma echinata. 

 Chewing apparatus, 



seen from within. 



£/, tooth-papilliB -, 



di\ teeth. 



