SYMBIOSIS 61 



Such is the frailty of life that the advent of better circum- 

 stances or of advantages due to ancestral efforts is frequently 

 made use of in a retrogressive manner, and is followed by a 

 relaxation of effort and an inclination to proceed along the 

 road of least resistance and of selfish expediency, until finally 

 the organism may cease altogether to contribute " a 1'entretien 

 de la vie generale." 



The animal first rendered strong by auspicious ancestral 

 dynamics proceeds to abuse its powers, and destroys and 

 devours the weaker instead of cultivating and protecting its 

 true complement. When in extremis of hunger and of bank- 

 ruptcy, it does not hesitate even to devour its own kith and kin. 

 The diathesis so produced in turn provides the soil for other 

 would-be profligates of every description. At the same time 

 the temptation is provided for certain plants to take the step 

 from cross-feeding (holophytism) to in-feeding (saprophytism), 

 which is certain to lead in turn to great changes in both plant 

 and animal kingdoms. In the case of the Convoluta partners 

 some of the algal cells became colourless and in that form 

 acquired the habit of obtaining food material after the manner 

 of an animal, i.e., they were on the road to lose their 

 characteristic photosynthetic capacity without any com- 

 mensurate permanent gain except perhaps indirectly in their 

 usefulness as scavengers. 



Whereas cultures of truly symbiotic plants are generally 

 seen to thrive best in mineral solutions, the case of Convoluta 

 presents the eloquent fact that: 



"Comparative cultures of the free stage of the infecting 

 organism have demonstrated that the alga flourishes better 

 when supplied with nitrogen in the form of uric acid than 

 when it is supplied with a nitrate (potassium nitrate)." 



The "infecting" algae, therefore, under the stimulation 

 provided by a retrogressive partner are definitely on the road 

 to the saprophytic character, the saprophytic diathesis. An 

 inferior physiological currency is ousting a former nobler 

 currency associated with strenuous character and photo- 



