THE CHARACTERISTICS OF ORGANISMS 27 



Enregistration.— A bar of iron is never quite the same after it 

 has been severely jarred; the "fatigue of metals" is one of the 

 serious risks of engineering; the violin suffers from mishandling. 

 But these are hardly more than vague analogies of the distinctive 

 power that living creatures have of enregistering the results of 

 their experience, of establishing internal rhythms, of forming 

 habits, and of remembering. As W. K. Clifford put it: "It is the 

 peculiarity of living things not merely that they change under 

 the influence of surrounding circumstances, but that any change 

 which takes place in them is not lost, but retained, and, as it were, 

 built into the organism, to serve as the foundation for future 

 action." We are not anticipating the question of the possible entail- 

 ment of individual acquisitions or modifications; we are in the 

 meantime keeping to the fact that the way in which an organism 

 reacts to stimuli is determined not only by the innate constitution, 

 but also by the accumulated experience of the whole and of the 

 parts during the individual lifetime. In various forms this is a 

 distinctive feature of the living creature. 



Evolution. — In the attempt to understand organisms we must 

 envisage them as a whole, we must see them in the light of evolution. 

 Thus it must be recognised as characteristic of organisms that they 

 give origin to what is new; they have evolved and evolution is 

 going on. There is variability in the crj^stalline forms which the 

 same substance may assume; the modern physicist tells us of 

 "isotopes" like the different kinds of "lead", which have the same 

 chemical properties, yet differ in the structure of the nucleus of their 

 atoms; the modern chemist even assures us of the transmutation 

 of elements, thus not a little justifying the medieval alchemists' 

 dream and quest. The synthetic chemist shuffles but a few mole- 

 cules, seldom going beyond Carbon, Hydrogen, Oxygen, and Nitro- 

 gen, and yet creates long successions of new dyes and drugs, new 

 perfumes and explosives. Yet these are only suggestive analogies; 

 for the living organism is the supreme, though unconscious, creative 

 chemist. 



No doubt there are species that show nowadays little or no 

 variation; there are conservative living types that seem to have 

 remained the same since their remains were first buried in the 

 mud millions of years ago, as in the case of the Cambrian Lamp- 

 shell Lingula, the Silurian Nautilus, and the Triassic lung-fish 

 Ceratodus ; but the larger fact is variability. In multitudes of cases 

 the offspring show something new. 



What impressions of variability we get at a "show" — whether 

 of dogs or pigeons, roses or pansies! Here we have, as it were, the 

 fountain of life rising high in the air — blown into strange forms 

 by the breeze, yet modulated, to its own ceaseless waxings and 

 wanings, by varying pressures from its source. Two hundred different 



V 



