200 ALONG THE FLORIDA REEF. 



but the common scallop dances through the 

 water by rapidly opening and closing its shell ; 



and when a party of 

 them start off they 

 look exactly as if they 

 were dancing through 

 the water. Many oth- 



Common salt-water mussel. er g^g fl oat along 



the surface, and depend upon the currents and 

 winds for their movements. The stilifer snail, 

 like one of Tom's pirates, boards the star-fish 

 and sea-urchins and is carried by them, while 

 many others are peculiar to the gulf-weed, and 

 either go the 

 grand rounds 

 with it or be- 

 come a fixture 

 in the great 

 Sargasso Sea. 

 But the great- The dancing scallops ' 



er number of bivalves are forced to lie in one 

 spot, trusting to the currents to throw food in 

 their way. Such are the oysters, and on some 

 grow spines that hold them so that the waves 



