M R. KARMEL'S carefuly analysis provides the basis for two statements which seem to me to summarize his criticisms. In the third from last paragraph he writes " . . . Dr. Whelpton's reproduction rates may be even more sensitive to fluctuations in marriage rates than the conventional reproduction rates and this seems to be a marked disadvantage."' In the next to last paragraph he writes "It follows that it is dangerous to draw the conclusion from Dr. Whelpton's calculations that the rise in wartime fertility in the U.S.A. has been larger even than that shown by the conventional net reproduction rates, and the principal purpose of this note is to draw attention to this fact." Although these statements may be true regarding the age-parity adjusted net reproduction rate in the frame of reference Mr. Karmel uses, I believe they are not true regarding the age-parity-fecunditymarriage adjusted rate.2 In what follows I will try to show that (1) the age-parity-fecundity-marriage adjusted net reproduction rate (assuming that 10 per cent of the women living to age 50 remain spinsters and 10 per cent of those who marry cannot have a child) is much superior to the age-parity adjusted net reproduction rate from a theoretical standpoint and should have been given much greater emphasis than the latter in my previous article, and neither (2) the first, nor (3) the second of Mr. Karmel's quoted statements is true for the age-parity-fecundity-marriage (81%) adjusted net reproduction rate.3