BRITISH ASSOCIATION. 315 



Having in view these and other considerations which might be 

 developed, I feel no reasonable doubt that though we may have to 

 forgo a claim to variations by addition of factors, yet variation 

 both by loss of factors and by fractionation of factors is a genuine 

 phenomenon of contemporary nature. If then we have to dispense, 

 as seems likely, with any addition from without we must begin 

 seriously to consider whether the course of Evolution can at all 

 reasonably be represented as an unpacking of an original complex 

 which contained within itself the whole range of diversity which 

 living things present. I do not suggest that we should come to a 

 judgment as to what is or is not probable in these respects. As I 

 have said already, this is no time for devising theories of Evolution, 

 and I propound none. But as we have got to recognise that there 

 has been an Evolution, that somehow or other the forms of life have 

 arisen from fewer forms, we may as well see whether we are limited 

 to the old view that evolutionary progress is from the simple to the 

 complex, and whether after all it is conceivable that the process 

 was the other way about. When the facts of genetic discovery be- 

 came familiarly known to biologists, and cease to be the preoccupa- 

 tion of a few, as they still are, many and long discussions must 

 inevitably arise on the question, and I offer these remarks to prepare 

 the ground. I ask you simply to open your minds to this possibility. 

 It involves a certain effort. We have to reverse our habitual modes 

 of thought. At first it may seem rank absurdity to suppose that the 

 primordial form or forms of protoplasm could have contained com- 

 plexity enough to produce the divers types of life. But is it easier 

 to imagine that these powers could have been conveyed by extrinsic 

 additions ? Of what nature could these additions be ? Additions of 

 material cannot surely be in question. We are told that salts of iron 

 in the soil may turn a pink hydrangea blue. The iron cannot be 

 passed on to the next generation. How can the iron multiply itself ? 

 The power to assimilate the iron is all that can be transmitted. A 

 disease-producing organism like the pebrine of silkworms can in a 

 very few cases be passed on through the germ-cells. Such an 

 organism can multiply and can produce its characteristic effects in 

 the next generation. But it does not become part of the invaded 

 host, and we cannot conceive it taking part in the geometrically 

 ordered processes of segregation. These illustrations may seem too 

 gross ; but what refinement will meet the requirements of the 

 problem, that the thing introduced must be, as the living organism 

 itself is, capable of multiplication and of subordinating itself in a 

 definite system of segregation ? That which is conferred in variation 

 must rather itself be a change, not of material, but of arrangement, 

 or of motion. The invocation of additions extrinsic to the organism 

 does not seriously help us to imagine how the power to change can 

 be conferred, and. if it proves that hope in that direction must be 

 abandoned, I think we lose very little. By the re-arrangement of a 

 very moderate number of things we soon reach a number of possi- 

 bilities practically infinite. 



That primordial life may have been of small dimensions need not 



