MULTIPLE CHROMOSOMES 547 



another. It is in full realization of this need for care in generaU- 

 zation that I wish to examine the conclusions of others regard- 

 ing chromosome numbers in the light of my own and my 

 students' studies. 



In making such an examination I can profitably take up 

 only the most general questions, because, in matters of detail, 

 it becomes a case of interpretation of phenomena, and many 

 times one is not justified in criticising the work of others without 

 himself knowing the objective conditions. For this reason I 

 should like to consider the work of Delia Valle on the subject 

 of chromosome numbers. I do not choose this author as repre- 

 sentative, because of any inherent strength apparent in his 

 papers, nor am I impressed by their niunber and size. On the 

 contrary they appear to me weak, because of the small amount 

 of observational basis and the large development of theory. For 

 instance in the paper of 1909 of the hundred and seventy-seven 

 pages, only forty pages are included under the heading "Data of 

 observation" and, of these, twenty are concerned with matters 

 of technique. Throughout all of his publications, indeed, there 

 is apparent a painful lack of judgment regarding the distinction 

 between fact and theory, and were he alone in his position he 

 could fairly be dismissed with little attention.^ 



' 'Objective analyses,' accomplished by the translation of morphological 

 facts into terms of physical chemistry, carry their own indictment of lacking 

 experience and judgment, and could safely be left without comment. Such 

 an attitude toward chromosome organization is, however, but an extreme case 

 of the position assumed bj^ a number of biologists who would seek to discredit 

 the hard won facts of cytology by an appeal to conditions or forces beyond ob- 

 servational control or by an arrogation of the whole problem to their own 

 chosen field. It Would seem that, in almost every case where such attitudes are 

 assumed, there is some animus or prejudice in the mind of the writer which be- 

 trays itself in his injudicious or intemperate language. All those who fail to 

 agree with his particular extreme views are depicted as banded together for the 

 establishment of dogma and the suppression of truth. With much vigorous 

 language and the plentiful use of exclamation marks all such are consigned to 

 scientific oblivion v.ith their obsolete methods and narrow views. 



This is very unfortunate. It is rarely the case that scientific investigators 

 are not honestly in search of the truth with regard to the subject of their en- 

 quiry, and to accuse them of conspiring for its suppression is most absurd. It 

 is true that new views sometimes prevail but slowly, but it does not hasten their 



