ANALYTICAL CHEMISTRY
38 (351) Shibata, S.,Takito, &I., and Tanaka, O., J . Am. Chem. Soc., 72,2789 (1950). (352) Smit, W. M., D i s c u s s i o ~ ~Faraday s SOC.,7,38 (1949). (353)Ibid., p. 248. (354)Ibid., p. 317. (355) Smith, G.N.,and Worrel, C. S., Arch. Biorhsm., 28,1 (1950). (356) Smith, J. D., and hiarkham, R., Biochem. J . , 46,509(1950). (357) Smith, J. R., Smith, C. R., Jr., and Dinneen, G. U., ANAL. CHEM.,22,867(1950). (358) Sober, H. A., Kegeles, G., and Gutter, F. J., Science, 110,564 (1949). (359) Solomons, I. .I and ., Regna, P. P.,J . A m . Chem. Soc., 72, 2974 (1950). (360) Spaeth, E.C.,and Rosenblatt, D. H., Science, 110,255 (1949). (361) Spedding, F. H., Discussions Faraday Soc., 7,214(1949). (362) Spedding, F. H.,Fulmer, E. I., Butler, T. 4.,and Powell. J. E., J. Am. Chem. SOC.,72,2349(1950). (363) Spedding, F.H., Fulmer, E. I., Powell, b. E., and Butler, T. .4., Ibid., 72,2354 (1950). (364) Srikantan, B. S.,and Krishnan, r*,,.J. Indian C h m 26, 415 (1949). (365)Ibad., 27,34 (1950). (366) Stadtman, E. R., and Barker, 13, A., J . Biol. Chem., 184,769 (1950). (367) Stepka, R., and Takahashi, W.N., Science, 111, 176 (1950). (368) Sternberg, J., and Demaux, G., Compt. Tend., 231,524(1950). (369) Stewart, A.,Discussions Faraday Soc., 7,66(1949). (370)Stoll, A.,Becker, B., and Helfenstein, A., Helv. Chim. Arlri, 33,313 (1950). (371) Stoll, A . , and Renz, J., Ibid., 33,256 (1950). (372) Stoll, A., Rutschmann, J., and Schlientz. IT.,I h i d . . 33, 375 (1950). (373)Strain, H. H.,AVAL. CHEM.,22,41 (1950). (374)Strain, H.H., I n d . Eng. Chem., 42,1307 (1950). (375) Strain, H. H., Science, 112,161 (1950). (376) Strain, H.H., and Sullivan, J. C., ANAL.CHEM.(submitted). (377) Street, K., Jr., and Seaborg, G. T., J . Am. Chem. SOC.,72,2790 (1950). (378) Stumpf, H.C., Russell, A. S., Newsome, J. W.,and Tucker, C. M., I d . Eng. Chem., 42,1398 (1950). (379) Tertian, R., Compt. rend., 250,1677 (1950). (380) Thompson, S. G., Cunningham, B. B., and Seaborg, (;. T., J . Am. Chem. SOC.,72,2798(1950). (381)Thorn, J. A.,and Johnson, M. J., Ibid., 72,2054(1950). (382) Tiseliua, A.,Naturwissenschaften, 37,25 (1950). (383) TiseliuB, A,, and Hagdahl, L., Acta Chem. Scand., 4,394 (1950). 1384) Tishkoff, G. N.,Bennett, R., Bennett, V., and Miller, L. L., Science, 110,452 (1949). (385)Tomkins, E.R.,Discussions Faraday SOC.,7,232 (1949). (386) Trevelyan, W. E.,Proctor, D. P., and Harrison, J. S., S r i l u r e , 166, 444 (1950). (387) Trueblood, K.N.,and Malmberg, E. W., J . Am. Chenz. Soc., 72,4112 (1950).
(388) Turba, F., and Enenkel. H. J., Natu,vissenschuften, 37, 93 (1950). (389) Turian, G.,Helu. Chim. Acta, 33, 1303 (1950). (390)Turner, R.B., J . Am. Chem. SOC.,72,579(1950). (391) Udenfriend, S.,and Gibbs, hi., Science, 110,708(1949). KoZZnidZ., 116,10 (1950). (392) Clmann, M., (393) Vahrman, & Nature, I., 165,404 (1950). (394) Tlscher, E.,Chargaff, E., and hiagasanik, B., Federation Pruc., 8,263 (1949). (395) Waddey, A. D., J . Am. Chem. Soc., 72,1781 (1950). (396) Walling, C.,Ibid., 72,1164 (1950). (397) Weiss, D. E.,Discussions Faraday Soc., 7,142 (1949). (398) Weiss, D.E., ;Vature, 166,66 (1960). (399)Weller, G.L.,Jr., Chromatography Bull., 1, 1 (1950). (400) Wendler, N. L.,Rosenblum, C., and Tishler, &I., J. Am. Chetn SOC.,72,234 (1950). (401) \Vestall, H. G., Nature, 165,717(1950). (402)Westphal, U., Gedigk, P., and hfeyer, F., Z. physiol. C ' h m . $ 285, 36 (1950). (403) Whistler, R. L.,and Durso, D. E'., J . A m . Chem. Soc., 72,67; (1950). (404) JYillianis, K. A., Discussions Faraday Soc., 7,264 (1949). (405) Williams, R. T.,and Synge, R. L. M., "Partition Chromatography," London, Cambridge University Press, 1949. (406) Wiridsor, E.,J . B i d Chem., 182,699 (1950). (40;) Willsten, W. A., Jarowski, C. I., Murphy, F. X., and Lazier, W.A , , J . Am. Chem. SOC.,72,3969 (1950). (408)\Vittenberg, J., and Sheinin. D., J . Biol. Chem., 185. l(l:3 (1950). (409) Woiwood, A. J., Yuture, 166,273 (1950). (410)Wolfrom, M. L.,and Montgomery, R., J . Am. Chern. ,S(,(.. 72, 2859 (1950). (ill) R'olfrom, h l . L.,Olin, Y. JI.. atid PolglaJe, W. J., Zbkl., 72, 1724 (1950). (412) Woodruff, H. B.,and Foster, J. C.,J . R i d . Chem., 183. 51,!4 (1950). (413) Work, E.,Nature, 165,74 (1960). (414) Panofsky, C., Wasserman. E., and Bonner, D. M., Sci?rm. 111, 61 (1950). (415)Yoshino, Y,, and Kojima, M.,13ull. Chem. SOC.Japarc, 23, 46 (1950). (416) Zaffaroni, .L, Burton, R . R., and Keutniann, E. H., Scierrcr. 111, 6 (1950). (417) Zechmeister, L.,Discussioru Faraday SOC.,7,54 (1949). (418) Zechnieister, L.,"Progress i n Chromatography 1938-1947." London, Chapman & Hall, 1930. (419) Zechmeister, L., and Rohdewald, h l . , Enzymologia, 13, 3% (1950). (420) Zimmerschied, W,J., Diiicrstein. I.ti-
(A pi,ol)lem is the discovery of a suitable system. I t woriltl therefore appear of interest to inc~itionthe most iniport:tnt considerations in making a choice. .inalytical extraction as