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ECHINODERMS: ECHINOIDEA. 



Fig. 462. — Holothurian, or Sea Cucumber. 



inch to several feet in length. They live in the sea 

 and are exceedingly interesting, and very beautiful 

 when the long and delicate fringes around the mouth 

 are expanded. When taken from the water they 

 shrink and lose their beauty of form and color. They 

 must be seen in the ocean, or in the aquarium, in order 

 to get a good idea of them. Figure 462 shows one 

 very common at Grand Manan, Eastport, and other 

 places on the North Atlantic. The Chinese use their 

 dried and smoked skins, called trepang, in making soup. 



SEA URCHINS, OR ECHINOIDEA. 



True Sea Urchins are hemispherical, or flattened, and 

 have a hard shell composed of plates which are regular 



Fig. 463. — Sea Urchin. 



in form and firmly bound together. Upon these plates 

 are tubercles, and on these tubercles hard spines, In 



