1907.] Mitosis in Proliferating Epithelium. 377 



portions of skin. The reduction mitoses were met with in those cases in 

 which proliferation was considerable, T5ut owing to the very large number of 

 division figures which are not sufficiently well defined to enable their 

 character to be determined, it is not possible to give statistics of the relative 

 frequency of the somatic and reduction mitoses occurring at different periods 

 in the proliferating epithelium. 



Summary. 



The preceding observations may be briefly summarised as follows : — 



1. In epithelial proliferation brought about by scharlach E, both normal 

 somatic and reduced mitoses occur. This statement applies to epithelium 

 proliferating in situ, and also to the same implanted under the skin. 



2. In the reduction mitoses the number of chromosomes which could be 

 counted varied from 14 to 18. In the somatic form the number counted 

 varied from 28 to 36. 



3. Eeduction mitoses could be recognised less frequently than somatic 

 mitoses. 



4. Post-reduction mitoses were met with. 



5. The character of the mitoses occurring was not definitely altered by 

 implantation under the skin. 



