RT Journal A1 STEMPFEL R, JR. T1 EMbryonic nutrition. JF A.M.A. Journal of Diseases of Children JO A.M.A. Journal of Diseases of Children YR 1959 FD September 1 VO 98 IS 3 SP 410 OP 410 DO 10.1001/archpedi.1959.02070020412017 UL http://dx.doi.org/10.1001/archpedi.1959.02070020412017 AB An interesting discussion of energy distribution in embryonic growth, differentiation, maintenance and functional activity is presented in a paper entitled "Embryonic Energy Exchange," by E. J. Boell. A chapter on "Metabolic Patterns in the Sea Urchin Embryo," by J. Lee Kavanau, again illustrates the value of this material in the quantitative investigation of embryonic metabolic processes; in this instance, exploratory studies into possible interrelationships between certain of the B vitamins and protein synthesis. "Yoke Utilization in Fishes," by Sydney Smith, is an excellent paper summarizing the author's vast experience in this area, in which the trout has been an ideal species for investigation. Immunobiological and immunochemical concepts of embryonic growth and differentiation are introduced in the paper "antigens as Tracers of Embryonic Synthesis," by James D. Ebert, in which the antigenic properties of embryonic tissues are discussed. Differences in quantitative demands upon the embryonic energy-substrate supply mechanism with the basic