EXTRACT XXVII. A. 



ON THE CELL, IN ITS GENERAL BEARINGS ON THE 

 EVOLUTION OF LIVING FORMS. 



THAT the cell, individually, and collectively, constitutes 

 the organic foundation of all living forms, may now be, 

 and, we may safely say, is admitted as axiomatic, and that 

 it affords not only, a theoretical, but a working, scaffolding, 

 on which we can, in safety, perform the duties of organic 

 science builders, with the maximum of success, and the 

 minimum of failure, has now been abundantly proved. 

 The cell individually, or the individual cell organism, has 

 performed, and continues to perform, the pioneer work of 

 organic life, claiming, from the inorganic matter of the 

 earth's crust, the materials, out of which it elaborates, by 

 vital energy, its distinctive protoplasm, clothing itself with 

 an outer, and differentiating, covering of that protoplasm, 

 which ensures the maintenance of its individuality, and the 

 power of perpetuating itself, by division, into still more 

 individual cells, which, by like divisional processes, con- 

 tinue the work, ad infinitum, an organic fact, which is 

 now being utilised for purposes of the greatest hygeinic 

 importance, as witness, the adoption of bacterial agency, 

 in the analytical treatment, and hygienic disposal, of 

 sewage. The cell unit, as witness the amoeba, while 

 thus living, acts by, and for, itself, and is characterised 

 by individuality of action, and merely accidental com- 

 munity of purpose, and represents the primary form of 

 cell life, i.e. it begins, and ends, in self, so far as it 

 individually is concerned, disappearing absolutely when it 

 has performed the functional role destined for it, but 



