A. E. Kriss, A. S. Tikhonenko and V. I. Biriuzova. Ultramicroscopic structures discovered in sea- and ocean-depths . . . . . . . . . . . . . . . . . 809

BOTANY

S. S. Khokhlov. Classification of apomixis in Angiosperms . . . . . . . . . . . 812

PLANT MORPHOLOGY

W. L. Vitkovsky. The ways of fasciation development in fruit- and small-fruit plants . . . . . . . . . . . . . . . . . . . . . . . . . 816

PLANT PHYSIOLOGY

G. M. Dobrynin. The roots of the Zea mays plant, and some of their typical features . . . . . . . . . . . . . . . . . . . . . . . . . . 819

L. I. Sergheeva and K. A. Sergheeva. The peculiar features of the annual cycle and frost resistance in arboreal plants . . . . . . . . . . . . . . . . 823

M. Kh. Chaylakhian and T. V. Nekrassova. Physiologically active substances as a means to surmount polarity in lemon cuttings . . . . . . . . . . 826

EXPERIMENTAL MORPHOLOGY

A. I. Matveeva. The dynamics of the regeneration process of the skull vault as brought about in dogs by the destruction method . . . . . . . . . 830

M. F. Nikitenko. On the rôle played by the central nervous system in the process of tail regeneration following autotomy in the lizard . . . . . . . . . 834

EVOLUTIONAL MORPHOLOGY

V. I. Strelkovsky. The ontogenesis of the opercular skeleton in Acipenseridae and the rôle it played in their phylogenesis . . . . . . . . . . . . . 837

CORRECTION

In my article published in DAN, vol. 111, No. 2, 1956 (Sh. S. Pkhakadze, “Certain propositions equivalent to the continuum hypothesis”), on p. 299 the last phrase of the fourth paragraph should read:

\(I_0^n\) is any (but once and for all fixed) continuum group of one-to-one transformations of the space \(\mathbf{R}^n\), satisfying the conditions: \(\Pi^n \subset I_0^n\), and the class \(D_0^n\) is \(I_0^n\)-invariant.

Sh. S. Pkhakadze

T-02691 Signed for printing 25 IV 1958. Print run 5400 Order 205
Paper size \(70 \times 108^{1}/_{16}\). Paper sheets \(6^{3}/_{4}\). Printed sheets \(18.5 + 6\) inserts. Publisher’s sheets 19.7
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