n 



LIVING MATTEE 57 



is associated with a considerable transpiration of water, by whicb 

 a large amount of heat is rendered latent, so that the plants 

 as a rule become cooler than their environment. But when tran- 

 spiration is checked, or when plants which are breathing actively 

 are observed, they are found to develop as much heat as animals. 

 For instance, on bringing together a mass of germinating peas, a 

 rise of temperature of some 2 C. above the surrounding atmosphere 

 can be detected ; a rise of 15 C. was measured in the large flowers 

 of the Victoria Regia. 



Lastly, it should be noted that if all animals live directly, or 

 indirectly, on the elements provided by the vegetable kingdom, it 

 is not, on the other hand, true that all plants live on the inorganic 

 substances provided exclusively by the soil, air, and water. A 

 great number of plants, lacking in chlorophyll, live saprophy tically 

 at the expense of the organic substances of plant residues and dead 

 animals, or parasitically at the cost of other living things. Such 

 are the Schizomycetes and Fungi, properly so-called. As the life 

 of animals is subordinated to that of plants, so the life of this 

 innumerable vegetable host is subordinated to that of animals or 

 other plants. 



VI. Since antagonism between the vital activities of plants 

 and animals is excluded, it follows logically that the functional 

 differences which exist between the two great kingdoms of living 

 Nature, and which are very apparent in the higher classes, must 

 consist in the different manifestations in the two kingdoms of 

 Metabolism, which underlies all vital phenomena. It is evident 

 that the anabolic processes are predominantly developed in plants, 

 the katabolic processes in animals. 



The fact above emphasised, that all animals require for their 

 nutrition organic matters (proteins, fats, and carbohydrates) 

 already formed by other animals or plants, shows that their 

 anabolic capacities do not extend to synthesis of these substances 

 from inorganic materials. The majority of plants, on the contrary, 

 can live and nourish on exclusively inorganic matter, showing 

 that their anabolic capacity is strong enough to enable them to 

 make this synthesis. 



The anabolic capacity seems to be most highly developed in 

 the group of the so-called nitrifying bacteria, which in recent 

 years have aroused great interest among physiologists. Devoid of 

 chlorophyll, they are none the less able, independent of the action 

 of the sun's rays, to form by synthesis all the organic substances 

 which they require for their development and reproduction, given 

 the inorganic materials provided by the soil and the air. More 

 wonderful still, some of them, on closer observation, are found to 

 be capable of synthetically forming organic nitrogenous matter by 

 absorption of free nitrogen from the air and soil. Among these is 

 Clostridium pasteurianum, studied by Winogradsky, which utilises 



