﻿OFIIIOMYXA. 



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the angular form of the upper arm-plates readily distinguish it fror 

 these latter, which have the plates considerably curved. 



LIST OF SPECIMENS. 



OPHIOMYXA Mull. & Trosch. 



Type of the Genus, 0. pentagona Mull. & Trosch. 



Disk and arms wholly covered with a thick, naked skin. No tooth- 

 papillae. Mouth-papilla3 and teeth in the form of flattened lobes, with 

 saw-like cutting edges. Arm-spines stout, bulging at the base, thorny 

 at the point, covered round the base wath thick skin ; near the tip of 

 the arm, the lower arm-spine has hooks along its edge. Arms rounded ; 

 arm-plates imperfectly developed. No tentacle-scales. Two genital 

 sUts, begmning outside the mouth-shield. 



SPECIES HEREIN DESCRIBED. 



OpMomyxa Jlaccida. 

 Ophiomyxa pentagona. 



