COMATULA. 183 



life free and peripatetic, is not only new, but without 

 any parallel in the whole range of the organized 

 creation. 



When therefore Mr. J. V. Thompson first described 

 the Pentacrinus Europceus, no person could have sus- 

 pected so anomalous and unexpected a result, as that 

 it was the young state of a Star-fish, the Comatula, an 

 animal easily procurable upon many parts of our 

 coast ; and to the structure of which we must next 

 turn our attention. 



The body of the Comatula (PL III. fig. 9) consists 

 of a small, circular, flattish disc, from the circum- 

 ference of which issue ten long pinnate rays, the ex- 

 panse of which, in a full-grown specimen, is at least 

 five inches, measuring from tip to tip of the opposite 

 extremities. 



The dorsal surface of the disc is provided with ten 

 or twelve slender organs, each terminated by a claw, 

 which from their action and use may be described as 

 claspers, as it is by means of these that the animal 

 fixes itself to foreign substances. 



The Comatula is, in fact, a star-fish, not only free, 

 but leading the most vagrant life of any of its tribe ; 

 at one time crawling about by means of its flexible 

 arms among submarine plants, at others floating to 

 and fro, adhering to their fragments by means of its 

 dorsal claspers, or even swimming about after the 

 manner of the Acalephse. In swimming, indeed, the 

 movements of the arms of the Comatulse exactly re- 

 semble the alternating stroke given by the Medusae 

 to the water, and has the same effect, causing the 

 animal to rise from the bottom and to advance back- 



