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Tin: AMERICAN NATURALIST | Vol. XLYI 



following' manner: Consider the determiner for some 

 detinite somatic structure in a germ cell of one parent 

 to be destroyed by an antibody analogously placed in 

 the germ cell of the other parent; this chemical reaction 

 must leave a product, which product it is conceivable 

 may cause considerable havoc in so intricate a mechan- 

 ism. There is no reason to believe that this product 

 would of necessity confine itself to reactions with de- 

 terminers first attacked ; it might indeed be conceived to 

 disturb or to destroy certain determiners for other 

 tissues and forms. 



The Silkie fowl seems to have received a very 

 severe and peculiar upset in its determiners for 

 pigmentation — note its black eyes and black deeply 

 seated body pigments, together with its "albinic" 

 plumage. Neither is there any probability, except 

 by chance, of parallelism or similarity between the 

 mechanical or chemical cause of such reaction and 

 the resulting determiners — a notion savoring some- 

 what of the earlier conceptions prevalent in some 

 quarters, of ante-natal influence — for Weismann 1 '' ex- 

 perimenting with Vanessa appears to have effected color 

 changes by means of temperature and Tower 20 to have 

 permanently upset that portion of the germ plasm of 

 Leptinotarsa determining pif/mentation by means of 

 humidity and temperature. Thus, units may be made 

 and unmade, and thus a foreign body or force entering 

 a germ cell may conceivably cause a long series of reac- 

 tions, each product becoming a new reagent affecting 

 the determiners of many forms and tissues, if by chance 

 lethal damage is not done before equilibrium is reached. 



Moore in his paper "A Biochemical Conception of 

 Dominance/' says : 



substances which are set free to react upon each otl 

 ""Germ Plasm," p. 379. 



