14 



GENERAL ANATOMY OF THE TISSUES. 



chemical and not physical, and still less vital. In opposition 

 to this view, however, Harting ('Ned. Lane' Sept. 1851), 

 observed, not long ago, the formation of pseudo-cells by the agi- 

 tation of albumen with mercury, in which case the albumen must 

 be solidified, in the same way as by the mere shaking with water 

 or otherwise, (Melsens, in 'Bull, de FAcad. de Belgique/ 1850. 

 Harting, &c.). Again, if by the bringing together of albumen 

 and chloroform, serum-casein and fat,chondrinand chloroform, — 

 albuminous, casein, and chondrin membranes are formed, as 

 Panum observed (see in part, ' Archiv f. Path. Anatomie/ iv, 2), 

 it can hardly be permissible to assume any chemical action.] 



H._OF THE CELLS. 



§ 7- 

 The cells, cellules, called also elementary cells, or nucleated 

 cells, are perfectly closed vesicles of 0-005 — O'Ol'" in mean 

 „. . diameter, in which we may dis- 



tinguish a special investment, 

 the cell membrane, and contents. 

 The latter are always composed 

 of a fluid, containing formed 

 particles of various kinds, and 

 a peculiar rounded body, the 

 cell-nucleus, which again con- 

 tains in its interior a fluid and 

 a still smaller corpuscle, the 

 nucleolus. These cells, which must be considered to be endowed 

 with peculiar vital powers, and to be capable of absorption and 

 assimilation, of growth and of multiplication, not only at the 

 earliest period, entirely compose the body of the higher and 

 that of most of the lower animals, but almost wholly generate 

 the higher elementary parts of the fulty-developed body. In 

 fact, even in adult animals, we find in very many places that 

 the elements are simply in the condition of cells, and that as 

 such they take a more or less marked share in the performance 

 of the organic functions. 



Fig. 1. Nerve-cells of the Thalamus opticus of man, — three of them having their 

 processes torn off. x 3.">(). 



