SOLAR FEATURES ASSOCIATED WITH ELLERMAN'S "SOLAR HYDROGEN BOMBS".

28 Pardee, A. B., F. Jacob and J. Monod, J. Mol. Biol., 1, 165-178 (1959). 29 Delbrftck, M., in Unitis biologiques douees de continuite g6nrtique, Colloq. intern. centre natl. recherche Sci. (Paris) 8, 33 (1949). Cohn, M., in The Chemical Basis of Development, ed. McElroy and Glass, (1958), pp. 458-468, suggests that the system referred to in notes 27 and 28 is an example of such steady states; but the proof that it operates in the cytoplasm and not at the locus of the gene is still lacking. 30 Ames, B. N., and Barbara Garry, these PROCEEDINGS, 45, 1453-1461 (1959); Jacob, F., Harvey Lectures (in press); Ephrussi, B., in Enzymes: Units of Biological Structure and Function (New York: Academic Press, 1956), Chap. 2; Vogel, H. J., in The Chemical Basis of Development, ed. McElroy and Glass (1958), pp. 479-484. 31 Nanney, D. L;, in The Chemical Basis of Heredity, ed. McElroy and Glass (1957), pp. 134-166. 32 Kalckar, H. M., M. B. Yarmolinsky, and H. Weismeyer, Science, 130, 1419 (1959). 33 Puck, T. T., J. cell. comp. Physiol., 52 (suppl. 1); 287-311 (1958). 34 For discussion of this problem see Sonneborn, T. M., in Genetics in the Twentieth Century, ed. L. C. Dunn (New York: MacMillan, 1951), chap. 14, and Danielli, J. F., Proc. Roy. Soc., B., 148, 321-331 (1958). Danielli's paper is based on studies of nuclear transplantation in Amoeba which should be called to attention in relation to nuclear differentiation in the frog, in Paramecium, and in Tetrahymena. 35 Schmitt, F. O., Proc. Amer. Phil. Soc., 100, 476-486 (1955); Nature, 177, 503-505 (1956); these PROCEEDINGS, 42, 806-810 (1956). 36 Breeding analysis is complete only in the case of double cells in ciliates; see Sonneborn, T. M. and R. V. Dippell, to appear in J. Exp. Zool. Other striking examples occur in Desmids; see Waris, H., Physiol. Plantarum, 3, 236-246 (1950). 37 Weiss, P., in The Chemical Basis of Development, ed. McElroy and Glass (1958), pp. 843-854.