DEFENSIVE FERMENTS OF THE ANIMAL ORGANISM IJ 



body have a common architecture, which is bequeathed 

 from generation to generation by means of the sexual 

 cells. The cells which combine into an organ have, 

 besides that, a structure specific for the organ. We 

 are bound to accept this view, otherwise it would be 

 incomprehensible why, for instance, the cells of the 

 liver should produce only bile, and the cells of the 

 medulla of the suprarenal bodies adrenalin, c. All 

 the cells of the body have certain functions to perform 

 which are of use to the whole organism. It is quite 

 certain that the different organs supply substances to 

 the blood, which set up definite processes in other 

 particular parts of the organism. If these substances 

 are to act effectively, they must have a definite specific 

 structure. The cells, too, on which they are destined 

 to act, must also be characterized by a special struc- 

 ture, otherwise it would be difficult to understand 

 why a special secretion acts only upon certain cells, 

 and leaves a number of other cells quite unaffected. 

 A particularly fine example of the specific action 

 of gland secretions upon cells of specific structure is 

 supplied by such cases of hermaphroditismus verus 

 as that, for instance, in which the bullfinch is found 

 to have a testicle on one side and an ovary on the 

 other. These peculiar animals have on the one side 

 ' male, and on the other female, plumage, each being 

 delimited accurately, and without any transition, along 

 the middle line of the body. It is absolutely 

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