44 



SEA-SHORE LIFE 



polyps. Others form hemispherical heads bearing beautiful star- 

 like polyps each having eight feathery tentacles, while still others 

 form the sea whips and sea fans so characteristic of an Atlantic 

 reef. In the sea fans, however, the polyps secrete a horny axis 

 which forms the internal framework of the fan and gives a tough 

 support for the fleshy parts which cover its surface. Nothing is 

 more strangely beautiful than these coral reefs where the rich pur- 

 ple sea fans and the chocolate sea whips wave gracefully to the 

 surges in the crystal depths, while brilliant fishes glistening in 

 green, blue, purple and yellow, glide in and out among the shad- 

 ows of the coral caverns. 



The precious coral of the Mediterranean is allied to the sea 

 whips. Its polyps are brilliant white, and have each eight feathered 

 tentacles ; Avhile the internal axis of the colony is red and stony. 



The Brown Sea Anemone, (Metridium marginatum, Figs. 19, 

 20), is our common sea anemone, which extends from New Jersey 

 to Labrador. It is abundant in tide pools, and upon the posts 

 and rock work of wharves in Long Island Sound, but it attains 

 a much larger size and more brilliant color north of Cape Cod. 



Fig. 20. UROWN SE.\-ANEJ10N'E, Contracted. Showing the white 



thiead-like tihtmeuts called acontia which are e.xtruded 



as a means of defense. 



Although usually brown in Long Island Sound, individuals of 

 a pure white, delicate salmon-pink, or olive, are common at Newport 



