OPIIIITRin.K. 



If) 



OPHIURID,^, 



OR SPINIGRADE ECHINODERMATA. 



These Starfishes are so named from the long serpent, or 

 worm-like, arms which are appended to their round, de- 

 pressed, urchin-like bodies. Naturalists have associated 

 them with true Starfishes, and made them a family of 

 Asteriadae ; but in reality they are as distinct from those 

 animals as they are from the Crinoid Starfishes. In fact, 

 they hold the same relation to the Crinoidese that the 

 true Starfishes hold to the Sea-Urchins. They are Spini- 

 grade animals, and have no true suckers by which to 

 walk, their progression being effected (and with great 

 facility) by means of five long flexible-jointed processes, 

 placed at regular distances round their body, and fur- 

 nished with spines on the sides and membranous tentacula. 

 These processes are very different from the arms of the 

 true Starfishes, which are lobes of the animal's body ; 

 whereas the arms of the Ophiuridte are superadded to the 



body, and there is no excavation in them for any pro- 



c2 



