180 SCIENCE PROGRESS 



structure, which is nothing but the expression of this activity. 

 Its identity as an organism is not physical identity, since from 

 the physical standpoint the material and energy passing through 

 it may be rapidly changing. In recognising it as an organism 

 we are applying an elementary conception which goes deeper 

 than the conceptions of matter and energy, since the apparent 

 matter and energy contained in, or passing through, or reacting 

 with, the organism are treated as only the sensuous expression 

 of its existence. Even the environment is regarded as in organic 

 relation with the organism, and not as a mere physico-chemical 

 environment. It follows that for Biology we must clearly and 

 boldly claim a higher place than the purely physical sciences 

 can claim in the hierarchy of the sciences — higher because 

 Biology is dealing with a deeper aspect of reality. It must 

 also be the aim of Biology gradually to penetrate behind the 

 sensuous veil of matter and energy which at present seems 

 to permeate the organic world at all points. 



This conception leads him to a conclusion on heredity in 

 which Mr. Francis Darwin's very word plant " memory " is 

 used, though with apology. 



If (he argued) it is a fundamental axiom that an organism 

 actively asserts or maintains a specific structure and specific 

 activities, it is clear that nutrition itself is only a constant 

 process of reproduction : for the material of the organism is 

 constantly changing. Not only is there constant molecular 

 change, but the living cells are constantly being cast off and 

 reproduced. It is only a step from this to the reproduction 

 of lost parts which occurs so readily among lower organisms ; 

 and a not much greater step to the development of a complete 

 organism from a single one of the constituent cells of an embryo 

 in its early stages. In all these facts we have simply mani- 

 festations of the fundamental characters of the living organism. 

 The reproduction of the parent organism from a single one of 

 its constituent cells separated from the body seems to me only 

 another such manifestation. Heredity, or, as it is sometimes 

 metaphorically expressed, organic memory, is for Biology an 

 axiom and not a problem. The problem is why death occurs, 

 what it really is, and why only certain parts of the body are 

 capable of reproducing the whole. 



The question of heredity held the field, and beyond all doubt 

 the most striking fact about the meeting was the universal 

 interest in the year's sum of work on the law of Mendel. The 

 Abbot of Briinn was as much the hero of the occasion as 

 Darwin ; and it is curious to remember that fifty years ago the 

 chief reason why the law was forgotten at its first publication 



