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THE AMEBIC AN NATURALIST [Vol. LTV 



transmissible it is usually held that in some mysterious 

 fashion it has so impressed itself upon the soma that it 

 becomes represented in the germ plasm by one or more 

 factors, determinants or genes which are able to repro- 

 duce the same character in the next generation. The 

 difficulties of conceiving this are so great as to convince 

 most students of its impossibility. On the other hand we 

 have to admit that we know little as to the means by 

 which a germinal factor arises and gains its expression 

 as a somatic character. Apart from the accessory chro- 

 mosome in sex cells and the highly suggestive work of 

 Professor T. H. Morgan and his associates on germinal 

 loci in Drosophila, we only know of factorial represen- 

 tation by somatic expression. We are ignorant of the 

 relationships between the two, and of the measures by 

 which one gives rise to the other. Were it not that Thom- 

 son has shown the contrast to be hardly justifiable, one 

 would be inclined to ask: Is it not as difficult to under- 

 stand how a genetic factor arises and comes to have 

 somatic expression as it is to conceive how germinal rep- 

 resentation may be gained by an acquired somatic char- 

 acter? We accept the one without demur, but are prone 

 to deny the oilier as impossible. We must not forget the 

 warning of Professor Lloyd Morgan that because the 

 phenomenon of acquired transmissibility can not be un- 

 derstood it is not necessarily rendered impossible. 



In considering the difficulty in the way of an acquired 

 character gaining factorial representation in the germ 

 plasm it is legitimate to enquire whether a transmissible 

 character is necessarily germinal as present-day teach- 

 ing so consistently affirms, that is, whether it is neces- 

 sarily represented in the germ plasm by definite genetic 

 factors. 7 We have admitted that we know little or noth- 



With the question of acquired characters before us there need be no con- 

 fusion as regards a germinal and a non-germinal character, and whether the 

 latter appears pre-natally or post-natally. On the considerations here set 

 forth a transmissible character is not necessarily represented directly by 



