GARDENS OF THE SEA 



193 



that is glassy, porcelain-like, or pearly. The 

 contours are always graceful ; and along the in- 

 ner walls the undulations of the shell surface 

 produce the most beautiful of all opalescent 

 hues. 



The univalves, as distinguished from the bi- 

 valves, have the single spiral shell. The spiral 

 is made up of mounting rings that usually turn 

 to the right. There are many of these gastro- 

 pods, but the great rose-colored stromb, called 

 a " conch " or a " queen conch," is the most 

 striking of the types. In poetry and painting 

 it is the "wreathed horn" of Triton; and in 

 prosaic every-day life aboard sailing vessels it 

 is still used as a signal-call and a fog horn. 

 The bivalves have two shells connected by a 

 hinge and ligament ; and that is the weak point 

 their construction. The star fishes, drum 



m 



fishes, drills, crabs, oyster catchers (not to 

 mention human beings) pry them open and 

 destroy them by millions. Nothing but rapid 

 breeding keeps the family from extinction. 

 And they are all beautiful in shell-form and 

 color. The pearl oyster, the mussel, the scallop, 

 the cockle do not exhaust the gamut of bivalve 

 splendor. There are others of the family, sel- 

 dom seen perhaps, that brought to the surface 

 are glowing in cells of opal, topaz, and ame- 



Beautrj of 

 the shell. 



Univalves 

 nrtd bi- 

 valves. 



Conches, 



oysters, 



clams. 



Scallops 

 and cockles. 



