The purpose of this experiment is to compare different concentration of epinephrineand shell debris for inducing clutchless oyster and discuss the posibility pond culturesystem.The experiment divided three parts:(1)At the larvae reached to 330-350μmperiod,treated with 0.05 mM,0.1mM,0.2mMepinephrine for one hour,after 48hours,to discuss the effect of epinephrine on the metamorphosis of oyster larvae.(2)Tocompare the metamorphosis for four groups,epinephrine,shell debris,epinephrine andshell debris,control.(3)Transfer the 0.3cm clutchless oyster into pond culture and indoorsystem.The shell length,total weight ,body weight,condition factor and mortality will bemeasured in every two week.