CELL THEORIES. 121 
5th edition, pp. cxv. and cxvi.). No doubt Dr. 
Sharpey distinguished clearly the nuclei “attached 
to the surface of the filamentous bundles or in their 
interior” from the rounded and oval corpuscles and 
irregular particles met with in the interstices of the 
tissue,’ which he said were “probably to be con- 
sidered as belonging to the interstitial fluid ;” but 
those who imputed importance to that latter variety 
of corpuscles had little help for it, at that time, but 
to associate them with nuclei. 
In the present day the protoplasmic element 
has assumed an enormous importance, casting the 
nucleus into the shade, while the reign of cell-walls 
has come to an end altogether. But to speak of 
life, as is sometimes done, as if it were an inherent 
property of a particular chemical substance, is 
surely going too far, and is a view which has 
nothing true in it which is not more than thirty 
years old; for it has long been familiar to every 
one that life never exists without the presence of 
nitrogenous substance of an albuminoid character ; 
and, though it has since been discovered that life 
in various instances exists in non-nucleated struc- 
tureless masses of protoplasm, that is a very different 
thing from life being a property of protoplasm. 
Further, it may very fairly be questioned if some 
of the simple organisms are not rather to be com- 
