NOTICE OF BOOK. 
DAS GLEITEE'DE WACHSTHUM BEI DEB GEWEBE- 
BILDXJHG DEB GEFASSPFLAIfZEH, Von Dr. G. 
KBABBE. Berlin, 1886. 
The existing investigations on the development of the tissues of 
plants have dealt rather with the course of the cell-divisions to which 
the different tissue-systems owe their origin, than with the peculiarities 
of growth by means of which the elements assume their permanent 
form. Of late years there has been a tendency, chiefly owing to the 
influence of Hofmeister and Sachs, to minimise the importance of the 
single cell, and to regard its growth as subordinate to, and dependent 
on, that of the whole organ to which it belongs. This view has 
undoubtedly received support from the recent researches on the 
continuity of protoplasm through the walls of cells. The brilliant 
results obtained in this direction by Gardiner, Russow, and others, 
seem to afford direct anatomical evidence of the mutual dependence 
of the constituent cells of a tissue 1 . A work, therefore, which is 
entirely devoted to the investigation of those changes in the tissues of 
plants which are due to the independent growth of their individual 
cells, claims quite exceptional interest. Such a work is the treatise 
by Dr. G. Krabbe on sliding growth in the tissue formation of 
vascular plants. 
The object of the present paper is to give a critical account of the 
more important results of Dr. Krabbe’s work on this subject, and to 
call attention to the conclusions which seem to follow from the facts 
that he has brought forward. 
By the term c sliding growth ’ those processes of growth are meant 
which are accompanied by mutual displacements of certain cells or 
groups of cells. The fact that changes of this kind occur during the 
1 See especially the introductory passage in Gardiner, Continuity of Protoplasm, 
in Phil. Trans. Royal Soc., Part iii, 1883, p. 817. 
