Report of the President 



89 



Ten scientific papers were published during the year in the 

 Anthropological Papers, by members of the de- 

 Publications partment stafL A full list of these ar ticles will 



be given under the head of Publications. 



ANATOMY AND PHYSIOLOGY 

 Department of Anatomy and Physiology 



Ralph W. Tower, Curator 



Early in the year it was decided to make an exhibit by 

 models of the development of the mammalian red blood cor- 

 puscles. Living cultures of blood-forming tissues were made 

 for the purpose of observing and recording the successive 

 stages in the production of the red cells— with the result that 

 the activities observed did not agree with the modern theories 

 and descriptions. Instead of seeing a small nucleated cell 

 remodel itself into a non-nucleated disk by extruding its nu- 

 cleus, we observed this same cell push out from its nucleus 

 round, straw-colored buds which finally floated off as true red 

 corpuscles. White cells of the lymphocyte series performed 

 the same function, and it is undoubtedly this process which has 

 been described as phagocytosis by most investigators during 

 the last 70 years. The idea of phagocytosis of red corpuscles 

 has remained unchallenged, since no method up to the present 

 time has been found by which it could be determined whether 

 the enclosed corpuscles were being devoured or being manu- 

 factured. By extended observations on the living tissue it 

 appears that the process is one of production of the red blood 

 corpuscle and not one of phagocytosis. The results of these 

 experiments show that : 



1. The red blood corpuscle of the mammal is the result of 

 nuclear budding and does not pass through a nucleated stage. 



2. The red blood corpuscle of the bird, which is nucleated, 

 is phylogenetically identical with the parent "normoblast" form 

 of the mammal. 



3. Phagocytosis of the red cells by the giant cells in normal 

 blood-forming tissue is not common, if it exists at all. 



