io SYMBIOSIS 



with the alga, depends upon the fungus' integrity as a worker 

 and cross-feeder. The more the fungus is able, with the aid of 

 the alga, to perfect its chemical specialism, the more this must 

 conduce to an enrichment of the protoplasm. Symbiosis, with 

 its necessarily implied "work," forbearance and restraint, is 

 therefore of immense importance in progressive evolution. And, 

 in general, the better the " sociological " conditions, the more 

 scope there is for physiological elevation. 



In the case of Convoluta referred to above, Prof. Keeble 

 points out that the relation between the coloured chlorophyll- 

 containing cells and the animal tissues presents the closest parallel 

 to the relation which obtains between the green and the non-green 

 cells of any chlorophyllous plant. What it points to is this : 

 that the relation between the parts of an organism, the so-called 

 physiological economy, is of a similar, if not identical nature 

 with that existing between separate individuals in Symbiosis. 



In a strenuous chlorophyllous plant, the more complete and 

 intense the internal Symbiosis, the more assured is the success 

 of the sexual mode of reproduction (as against the mere asexual 

 or seedless method of propagation) ; and it is to the sexual method 

 more particularly that we owe the most ideal productions of 

 the plant. The. asexual method, though common enough, does 

 not represent the highest symbiotic potentiality of the species, 

 but appears rather as an inferior method, necessitated by special 

 conditions of existence. It stands to reason that those of the 

 non-green cells of a strenuous chlorophyllous plant which are 

 to perform the exacting duties of sex, require in turn the utmost 

 co-operation from other cells, tissues and organs. These exacting 

 duties of the sexual cells involve the accomplishment of complete 

 pro-creation with its concomitant demand of a provision of 

 a considerable amount of embryonic and post-embryonic equip- 

 ment of the new organism. And they involve, moreover, as an 

 indispensable bio-economic concomitant, the simultaneous 

 accumulation of biological exchange capital. For, in order that 

 the race may prosper and the labours of sex be not in vain, 

 provision must be made, over and above embryonic nutrition, 

 for cross-pollination and seed-dispersal. And this contingency 

 requires a permanent symbiotic relation with biological " helpers " 

 or " partners," who in turn require (such are the dictates of 

 " natural Ethics ") to be adequately " paid." The plant is 

 called upon to provide " remuneration," or " offerings " adequate 



