Abstract:The author discussed Cui and Lawson's mistakes from neglecting μc =μmXm/ X'm in their paper(Cui and Lawson,1982), as a result of that,their method and conclusion are incorrect,and their moded is not a generalization of the exponential and logistic equations.Because μc=μmXm/Xm' if X'm>>Xm,Cui-Lawson's model dX/Xdt=μc(1/x/xM)/(1-x/x'm) will not reduce to logistic form,but to dX/Xdt=0.
