THE CATALYST ENTELECHY IN DIFFERENTIATION 195 



he states: "All points taken together suggest strongly that the 

 chromosome is the actual heredity unit controlling the develop- 

 ment of the Wild type, that purely steric changes 30 at the indi- 

 vidual points of its length produce deviations from the Wild 

 type which may be described as mutations, even as point muta- 

 tions, though no actual Wild-type allelomorph and therefore no 

 gene exists." "If the chain is intact, and each residue is in its 

 proper steric position, the catalytic processes dependent upon 

 this chain molecule occur in a way that leads to what is called the 

 Wild type. Any change in the chain, however, of whatever type, 

 may disturb the interplay of the catalyzed reactions, and a devia- 

 tion occurs which is called a mutation." The final words of his 

 book are: "It remains for the physico-chemist to decide whether 

 or not the new model could also take care of the independent 

 catalytic actions of what was considered to be a gene." 



The structural and mechanically operative nature of the 

 chromosome is not made clear, nor is it fairly expressed by the 

 words "a large chain molecule of complex arrangement." Work 

 with the various textile fibers 31 indicates that in them there are 

 many structural levels above the macromolecular chains, and that 

 these chains form bundles which in turn are bound into still larger 

 micells, probably in part by the cohesive action of adhering sub- 

 stances and by interpenetrating fibrils. Whatever the structure 

 of the chromosome, it seems to be more complex than a simple 

 protein chain molecule of the nature described by M. Bergmann, 

 even though many such molecules may be in the chromosome. 

 Goldschmidt's abandonment of the gene is rather verbal than 

 factual, for even if considered as a side-chain in a macromolecule, 

 it is still there as a specific atomic complex. His views have been 

 adequately critized by Dobzhansky. 32 



It is, however, encouraging to see that so eminent a biologist 

 as Goldschmidt appreciates the biological importance of catalysis, 

 even though his language seems to limit it to the gene. In deal- 

 ing with embryological questions he fails to invoke catalysis. His 

 quandary regarding the position effect of rearrangements is readily 

 clarified by the fact that the genes, as well as many other biological 

 units such as the enzymes, exert their specific catalytic effects be- 

 cause of their outwardly directed electronic fields, and the ques- 

 tion of importance is the nature and directive power of these 

 fields rather than the terms we use to describe the units which 

 establish the fields. Thus three units CAT would exhibit dif- 



