ECHINODERMATA 87 



River, Delaware, in about 110 feet of water where the 

 bottom temperature is unusually low. It rarely 

 reaches 4 inches in diameter this far south. 



Astropecten americanus Verrill 



PLATE VI. Fig. 8 



Body flat, the arms long', narrow and sharp- 

 pointed bordered with a row of conspicuous large 

 plates; color yellow. 



A common starfish of deep water: known to live 

 75 miles off Cape May; occasionally brought in by 

 the deep sea fishing boats. 



OPHIUROIDEA 



(Brittle Stars or Serpent Stars) 



The animals of this group differ from the true 

 starfish (Asteroidea) in that the arms are quite di- 

 stinct from the body and there are no extensions of 

 the body organs into them. These arms are very 

 flexible and serpent-like, hence the name Serpent 

 Stars; also they break readily, hence the name 

 Brittle Stars. 



These animals move aboirt fairly actively and at 

 the approach of the slightest danger they throw off 

 one or more of their arms. They, however, possess 

 the power of regeneration and the missing parts are 

 soon replaced. 



