ECHINODERMATA. 



381 



its wants and instincts. Small Mollusca and Crus- 

 tacea appear to be its chief diet ; and if an ani- 

 mal of this kind be but touched by one or two of 

 the sucker-feet, its doom is sealed; the hold is 

 never relinquished, other suckers are applied to it 

 until it is passed round to the mouth, whose formi- 

 dable jaws are able to crush the stony shell, or 

 crustaceous covering. 



ECHINODERMATA. Fig. 1. Echinus; 2. Scutella; 3. Asterias ; 

 4. Opldurus; 5. Gorgonocephalus ; 6. Comatula ; 7. Encrinus. 



From this rounded form, other species, more and 

 more flattened, gradually lead to the genus Scu- 

 tella,* which takes the form of a thin round plate, 

 * Scutella, a dish like a shield. 



