The Scope of Natural Selection. 
Continued from page 129. 
By J. LIONEL TAYLER. 
The Primitive Characteristics of Protoplasm. 
In this section I wish to briefly recapitulate a few well-known 
facts and generalisations, which appear to me to lead to the 
conclusion that natural selection acting on variations has been the 
sole means of producing divergence and evolution in the organic 
world, that protoplasm is never really modifiable, although it may be 
and has been adapted to a marvellous degree. 
In the evolution of organisms certain generalisations have been 
shown to be in the main true. From the lower to the higher forms 
organisation tends to grow more complex and also more specialised ; 
this development consists in a qualitative and a quantitative change. 
In estimating the value of any theory which claims to be able to 
largely explain the process of evolution this quantitative, as well as 
the qualitative, change must be kept in mind. If a study of the 
lower forms of life leads to the conclusion that even here elimination 
brings about adaptation, and that there is little or no evidence for 
modification of structure, while when we compare the higher and 
lower forms we find that the differences are very largely due to an 
increase in complexity, and that the qualitative difference is merely a 
further development or accentuation in the more advanced organism of 
a property which is always present in the less advanced, then it will 
be evident that the facts are largely in favour of a purely selectionist 
theory of evolution. That a study of the facts does lead to such a 
conclusion I shall now endeavour to demonstrate. 
In the lowest forms of life we are confronted with a kind of sub- 
stance (protoplasm) which manifests certain peculiarities which 
appear at first to sharply distinguish it from inorganic material. 
Protoplasin from its commencement, as far as we are able to examine 
it, appears to exist in two more or less distinct forms; these forms are 
not sharply marked off, but more or less shade into each other, but 
still are sufficiently clear and distinct to have led apparently to widely 
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