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Dzicllcrs of the Sea and Shore 



their ancient habits is not in any sense to be taken as 

 a form of degeneracy; they have, on the contrary, ac- 

 quired an uncommon degree of specialization in order 

 to adapt themselves to an aquatic existence. 



Like the seaweeds, these plants are intrinsically in- 

 teresting, but they are especially noteworthy for their 

 remarkable association with certain forms of animal 



PRICKLY wort; a FLOWERING PLANT OF THF. SEASHORE. 



life. Seldom do we find a bed of eelgrass (Zostera) 

 without a host of hydroids, snails, and other creatures 

 living among its watery glades; even one or two red 

 algs seem to prefer the slender leaves for their attach- 

 ment rather than the rocks. The thatch (Spartina) 

 and other plants of salt marshes anci meadows are 

 marked by some crustaceans as their very own. A 

 species of fiddler crab {Uca pugilator) makes its home 

 in such numbers in the muddy soil holding the thatch, 



