CLAMS, OYSTERS, AND MUSSELS 



ll;i 



the mud within reaeli of the sea water. In tliis position a 

 stream of sea water carrying f(.)oil and air goes down one 



tuh)e, is (hiven tlirougli the gills, 



and finally l)ack up the othci 

 tube to 1)6 poured into the sei 

 above. 



Oysters. — They are siniilai m 

 structin-e to a mussel, exc< pt 

 that tlu^y liaA'e no foot, or only a 

 rudimentary one, and no siphons, 

 and the A'alves of the shell are 

 une(iual. One A'alve is hollowed 

 out to receive the l)ody of tlie 

 oyster, and the other xalve is 

 nearly flat. Usually the liollow 

 valve is attached to some sul)- 

 merged object. They live all 

 along the Atlantic coast south ol' 

 Cape Cod, and along the Gulf 

 coast. Oysters are, i3rol>abl\ 

 most extensively grown in th( 

 Chesapeake Ba>'. Their egt,s - 



which are produced in gn it 

 f[uan titles, soon hatch, and, alt( 1 -^ •- 



a few days of a free-swinuning Fig- go. 

 life, the young oysters attach 

 themselves to some objects, usually ol<l shells, and begin 

 growing in earnest. It takes an oj^ster from three to five 

 years to become of marketable size. In making artificial 

 beds, old shells, pieces of earthenwa.re, and slate are thrown 

 into the water for places of attachment for the oysters. 

 Oysters li\'e on nhmde ]")lants and animals found m fresh 



IIEHRH k's zool.. 8 



-1, 'SSJ '...tit? 'I 



JsUr "S'-s- JS?'- <■ 



— Long clam in its 

 burrow. 



