24 DEFENSIVE FERMENTS OF THE ANIMAL ORGANISM 



or even more precisely, ' with the cells " ; or ' with 

 the blood.' Substances that are specifically elabo- 

 rated for the blood would then be " out of harmony 

 with ' the cells, and conversely the substances ' in 

 harmony with ' the cells are " out of harmony 

 with ' the blood, or better, with the plasma, because 

 the components of the form elements of the blood 

 are out of harmony with the plasma, and inversely. 

 Products in harmony with the cells will only be 

 in harmony with one another in so far as they belong 

 to cells with similar functions, so that from this 

 point of view, for instance, the specific elements 

 of the thyroid gland must be regarded as out of 

 harmony with those of the suprarenal bodies, and 

 inversely. The idea of an entirely specific structure 

 for each cell of an organ both from the chemical 

 and physical points of view is based not only on 

 the supposition that, without such a notion, the 

 special duties and functions of the separate cells of the 

 body would appear incomprehensible, but, above 

 all, on the above-mentioned fact that definite 

 secretions given off by particular organs act con- 

 stantly and only upon cells of a definite system. 

 This implies that the cells in question must have a 

 structure which distinguishes them sharply from all 

 other kinds of cells. 



The view that each animal species is capable of 

 building up complicated compounds of peculiar 



