328 



TllK AMEIllCAX XATUBALIST [Vol. LI 



the production of enzjines, which, in turn, regulate cer- 

 tain aspects of the development, is a common one.^^ 

 Several Mendelians have even hinted that the "unit charac- 

 ters" themselves are enzymes,^ ^ but so far as I am aware, 

 no worker in genetics, with the exception of Groldschmidt, 

 has regarded this conception as an imj^ortant one.^^ In- 

 deed, in the face of the nearly self-evident, they have 

 turned away to vitalism and despair. 



Consider, for example, the following quotation from 

 Bateson. 



We must not lose sight of the fact that though the factors - operate 

 by the production of enzymes, of bodies on which tliese enzymes can 

 act, and of intermediary substances necessary to complete the enzyme 

 action, yet these bodies themselves can scarcely be genetic factors, but 

 consequences of their existence. What are the factors themselves? 

 Whence do they come? How do they become integral parts of the 

 organism? Whence, for example, came the power which is present in a 

 White Leghorn of destro>-ing— probably reducing— the pigment in its 



It is my contention in this and previous papers that 

 statements of this sort can hardly represent anything 

 less than intellectual blindness. On the supposition that 

 the actual Mendelian factors are enzymes, nearly all of 

 these general difficulties instantly vanish, and I am not 

 acquainted with any evidence which is inconsistent with 

 this supposition. 



Ill 



Up to very recent times, although a great number of 

 hypotheses to explain catalysis were in existence,^ no 



11 See, for example, the following: Loeb, J., and Chamberlain, M. M., " An 

 Atteriipt at a Phvsieo-Chemical Explanation of Certain Groups of Fluctuat- 

 ing Variation?," Jounial of Exptrtmi vtal Zoologn (li)M). 10, 3.-i9-568. 

 Moore, A. R., "On Mendelian Domiiianoe," Archiv fiir Entwicklungs- 

 mcclmnik (1912), 31, 1(38-175. Eiddle, O., "Our Knowledge of Melanin 

 Color Formation and its Bearing on the Mendelian Description of Hered- 

 ity," Biological Bulletin (1908), 16, 31(5 ff. 



12 See Bateson, "Mendel's Principles of Heredity," 1909, 268. 



13 The speedy j.ublic'dion of exiH riniental results of great importance in 

 this connection is i)roMiiM:d hv ( ioMM-hmidt. See above references. 



i4Bateson, "ProMrn.s of (U-ncti.'s" s<i.^ 



and fermentation is ^Weu l-y Moilor, J. W., "Chemical Statics and Dy- 

 namics," 191-1, 245-383. 



