SYMBIOSIS AND THE BIOLOGY OF FOOD 261 



it is also useful to life generally, it is clear that every organism, 

 however humble, which is engaged in Symbiosis, is contributing 

 to the general welfare of life. It may justly be said that sym- 

 biotic organisms are good citizens in organic civilisation. 



The Economy of Nature, as evidenced by the totality of 

 the phenomena of Symbiosis, shows that there is indeed an 

 important fundamental Sociology of Nature, which can on no 

 account be neglected. No one, in dealing with such phenomena 

 as Symbiosis and Parasitism, can help using sociological terms. 

 The use of such terms, however, is generally implied to be but 

 metaphorical, or, at least, only provisional. My contention is 

 that there exists a very actual and very real Sociology of Nature, 

 and this truth is to some extent to be established in this paper. 



What is involved in Symbiosis is this : a kind of marriage, 

 a continuous do ut des, a mutual industry entailing moderation 

 and restraint in many ways. The symbiotic life may therefore 

 be regarded as providing early physiological, psychological, and 

 even moral, or at least bio-moral, training of the organism — 

 a schooling in fair dealings, in physiological and biological 

 righteousness, in short, in character. The biological is, of 

 course, inseparable from the sociological interpretation. 

 That this is so may be gleaned from a definition of protoplasm 

 as supplied by Geddes and Thomson as of " a successful firm 

 which owes its success to an unusually fortunate combination 

 of partners — of inventive, organising, administrating, pushing, 

 competitive, and other geniuses — a firm unified from within, 

 whether by a common purpose, or by the predominant will of 

 its leading partners, or by something of both " (the internal 

 unity being far from being understood). 



This is, of course, only a comparison, calculated to emphasise 

 how largely and fundamentally biology is a science of behaviour. 

 The constitution of protoplasm may well be subject to cosmic 

 laws at present beyond our ken. Meanwhile, we shall probably 

 not be wide of the mark in viewing protoplasm as constituted 

 by a kind of Symbiosis on the part of the " life-elements." 

 Not any and every kind of union of the " life-elements " can 

 constitute protoplasm, any more than any and every biological 

 union can constitute Symbiosis. Qualifications of special 

 serviceability are required in each case. An all-essential 

 legitimacy or " integrity " is required in each case if abiding 

 results are to ensue. The study of Symbiosis clearly brings out 

 the fact that there are ways and methods of life which tend 

 towards progressive modifications of the protoplasm, in con- 

 trast to other modes which have the opposite effects. We know 

 that all species in nature have their own protoplasm. But 

 these protoplasms are not equally viable and resisting to disease. 

 We know, further, that the multiple ingestions and (proteid) 



