276 A. RICHARDS. 



chemical sense where two phases exist in the same cell, and where 

 there must be interaction between the constituent parts of the 

 system, and in a mathematical sense of unchangeableness) and 

 to the more deeply grounded objection that the process is one of 

 dynamic character and is not subject to morphological explana- 

 tion. 



Mathew's objection is perhaps the most significant of the 

 first group. He says "All so-called nuclear stains of basic 

 nature except the mordanted stains as iron hsematoxylin com- 

 bine with nucleic acid. Cytologists in following chromatin and 

 chromosomes may be following only the inert skeletal material 

 of the nucleus while the active albuminous material is entirely 

 neglected since it does not gel or stain with basic dyes." Yet 

 significance must attach to the constant recurrence of these 

 structures whether they are of skeletal nature or otherwise, and 

 to the fact that chromosome structures reproduce themselves and 

 have done so indefinitely. If they are not more than skeletal in 

 nature, they are at least the manifestations of the "protein or 

 basic" and perhaps more active parts of the cell, and the corre- 

 lation is so close that their behavior is no less significant. 



Pick's objections as Wilson has pointed out refer only to the 

 strict interpretation of individuality which is not supported by 

 the evidence and which is no longer held by cytologists in general. 



With regard to the morphological method of attack as one 

 means of studying dynamic problems more is to be said in defense 

 than against. The nucleus is, indeed, "a dynamic system," as 

 one of the chief critics of the continuity hypothesis has pointed 

 out; and the process by which it reproduces itself is of all bio- 

 logical phenomena the best example of a dynamic process. Yet 

 a dynamic process whose basis is not material, indeed not morpho- 

 logical, is only with difficulty thinkable. In whatever may be 

 the final terms of our thinking, chromosomes, chromomeres, 

 molecules or ions, we deal in the end with structure and con- 

 figuration; and this fact must make us hesitate in any attempt to 

 detract from the significance of chromosome structure and con- 

 tinuity. We may believe consistently that the chromosome is a 

 continuing structure, and that its correlations with processes of 

 heredity are even so close as to be causal, without forgetting that 



