MICROBIOLOGY

L. A. Galanina, P. A. Agatov. The influence of substances containing the guanidine or ureal group on the formation of streptomycin by the LC-1 strain of Actinomyces streptomycini . . . . . . . . . . . . . . 1413

BIOPHYSICS

V. P. Paribok, E. I. Genter. The role of oxygen replacing gas in the course of quantitative investigation of the oxygen effect . . . . . . . . . . . 1416

E. K. Putseiko. A spectral investigation of the photogalvanic effect in films of zinc tetraphenylporphine on polarized electrodes . . . . . . . . . . 1419

BIOCHEMISTRY

E. A. Boichenko, V. E. Zarin. Iron combining with coenzyme A in plants 1423

R. N. Glebov, G. N. Zaitseva, V. P. Ermishkin, A. N. Beloserskii. Certain data on the “degeneration” of lysine sRNA as connected with the degeneration of the code . . . . . . . . . . . . . . . . . . . 1427

N. A. Gumilevskaia, E. B. Kuvaeva, L. V. Chumikina, N. M. Sisakian. A study of the microsome and ribosome of the silk-excretory gland in Bombyx mori L. . . . . . . . . . . . . . . . . . . . . 1431

V. B. Evstigneev, V. A. Gavrilova. Electrode active primary oxidation form of chlorophyll . . . . . . . . . . . . . . . . . . . . . . 1435

V. P. Zykova, T. S. Pashkina. The discovery of the kallikrein in the γ₁-globulin fraction of the proteins of the rabbit blood serum . . . . . . . . 1439

PLANT PHYSIOLOGY

M. Kh. Chailakhian, M. M. Sarkisova. The dynamics of natural gibberellines in seedless and seed-bearing grape-varieties, with reference to the effect of gibberellic acid . . . . . . . . . . . . . . . . . . 1443

M. J. Shkol’nik, V. P. Bozhenko, T. S. Momot. Increase in heat-resistance of wheat-sprouts by treating the seeds with solutions of aluminium and cobalt salts . . . . . . . . . . . . . . . . . . . . . . 1447

PHYSIOLOGY

Iu. M. Burmistrov, Zh. P. Shuranova. A study of the synaptic mechanism of photostimulation of the muscular fibre . . . . . . . . . . . . 1450

LETTER TO THE EDITOR

The result of my article (E. A. Loginov, “On a proper three-color coloring”), published in Doklady Akademii Nauk, vol. 163, no. 3, 1965, as later became clear, is not new.

The general theorem formulated at the end of the article was proved as early as 1940 by R. L. Brooks (On colouring the nodes of a network. R. L. Brooks. Proceedings of the Cambridge Philosophical Society, vol. 37, p. 2, 1941, 194—197).

I deeply regret the lack of awareness I showed. I thank comrades V. L. Dunin-Barkovskii and A. A. Zykov, who drew attention to my inadvertent omission.

E. A. Loginov

T-16472. Signed for printing 11/XII-65. Print run 4315 copies. Order 3137.
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