24 RADIOiJENESIS IX EVOLUTION. 



been esta])li,shed arouiicl the facts of variation. Through 

 studying tliese, Kadiogenesi.s came to inind as a suggestive 

 term for epitomising certain complex phenomena. In some 

 res])ects it escapes many of the objections Avhich have been 

 raised against the commonly-used Orthogenesis, and it 

 has the advantage, to my mind, of not bearing so definite 

 a teleological interpretation. Hence the title of this 

 paper. And as it is obviously impossible to isolate one 

 phase of Evolution, the writer feels that no ajjology is 

 needed for touching, even though very casually, on other 

 points. 



In some quarters there is a tendency, which is by no 

 means new, to postulate universal laws as the result of a 

 few experiments and observations. In several instances 

 this is doubtless justifiable, but it is becoming more and 

 more apparent that generalisations which may seem to 

 govern certain sets of phenomena may not be arbitrarily 

 applied as laws throughout the realm of nature. In 

 science, as in politics and other schools of life, loyalty to 

 an attitude or a theory tends sometimes to develop a species 

 of dogmatism which, occasionally, creates .strenuous 

 controversies. 



Many instances may here be given. Let us take first 

 the unceasing discussion of the inheritance of acquired 

 characteristics. Weismann distinguishes acquired character- 

 istics as somatogenic, denoting that such arise 

 only through special influences affecting the body or 

 individual parts of it ; in contradistinction to these are 

 blastogenic characteristics which originate solely in the 

 primar}^ constituents of the germ. With Wallace, Ray 

 Lankester. J. Arthur Thomson and others, he holds that 

 acquired characteristics, as so defined, cannot be trans- 

 mitted to offspring, and so far as negative evidence goes, 

 the position is a strong one. Lankester, it should be noted, 

 believes in the transmittance of Avhat he suggestively terms 

 '• educability,"* and thus his attitude is somewhat 

 qualified. The Neo-Lamarckian school strongly criticises 

 the view that acquired characteristics are not transmitted, 

 and Haeckel firmly sup])orts them here. Dendy has also 



*P»-»B. Address, Brit. Association, York, 1906. 



