Further observations on Chromosomes and Sex- 

 determination in Abraxas grossulariata. 



By the late 



Professor L. Doncaster, F.R.S., 



University of Liverpool. 



The following paper was left by the late Professor Doncaster 

 in an incompleted condition, and, as I was one of his assistants 

 during his last year's work, it has been entrusted to me to 

 prepare for publication. 



The paper as it now stands is exactly as Professor Doncaster 

 left it, except that I have added the account of the staining 

 methods used to test the nature of the elimination plate. I was 

 familiar with his staining methods because I was myself testing 

 for chromatin in some entirely different work when Professor 

 Doncaster was testing the elimination plate, and he kindly 

 passed on all his stains to me as he used them, showed me 

 his preparations, and discussed the whole matter with me. 

 In his rough notes I find a full account of all the stains used, 

 and carefully labelled figures showing the results obtained from 

 the different staining methods : there is, therefore, no uncer- 

 tainty about the facts which I have added. 



A summary of the paper included amongst Professor 

 Doncaster 's rough notes shows that he intended to add three 

 other sections on ' Conjugation, &c., of polar nuclei ', ' Binu- 

 cleate eggs ', and ' Gynandromorphs '. These sections were 

 unfortunately not written even in note form, and therefore 

 cannot possibly be produced ; but the paper as it stands is 

 of such obvious interest that its publication even in this very 

 incomplete form is more than justified. 



EUTH C. Bamber 

 (Mrs. Bisbee). 



NO. 263 F f 



