General Physiology of Animals. 341 



P represents the fully formed living protoplasm (animal) 

 occupying the centre of two sets of diverging lines. On the 

 left hand the ultimate food- stuffs are represented as being 

 built up into intermediate products, which may be known as 

 mesostates, while on the right hand protoplasm is repre- 

 sented as undergoing katabolism, where some of the inter- 

 mediate stages are of service in the body (secretions) 

 although ultimately they are all got rid of as katastates or 

 excretions. Of course the same diagram might apply to 

 protoplasm of green plants, although in that case the ulti- 

 mate food-stuffs would be inorganic only. Combining both 

 diagrams, and at the same time varying the character of 

 the figure itself, we might graphically summarise the meta- 

 bolism of both plant and animal in relation to the organic 

 world thus : 



FIG. 192. 

 ANIMAL PROTOPLASM 



INORGANIC WORLD 



The diagram is, indeed, only a variation on that import- 

 ant scheme on which so much emphasis was laid at p. 49. 

 The separate steps stand for anastates and katastates, while 

 the anabolic stair for animal protoplasm is made to spring 

 from near the top of the katabolic vegetal stair as indicating 

 that the animal is dependent on the plant for food. 



We must now glance for a moment at the results of the 

 metabolism of animal protoplasm. The more important of 

 these may be classified under growth, motion, nervation, 

 heat, light, and electricity. Reproduction or the separation 

 of sexual cells has already been sufficiently considered 



<p 52). 



