Zool.— Vol. I.] EISEN—PLASMOCYTES. 6l 



some, and the cytosome; but of course I do not claim that 

 it proves it. The effect of such a symbiosis would be, 

 among other things, to create a cell membrane and cell 

 division by mitosis. I favor this theory because it explains 

 the survival of the archosome (surrounded by cytoplasmic 

 envelopes) as an independent corpuscle. 



16. The new plasmocyte in the blood of Batrachoseps 

 may then be denned as a corpuscle, generally without a cell 

 wall and always without a nucleus; but consisting of the 

 archosome, which has surrounded itself with the three outer 

 spheres of cytoplasm, and which survives as an independ- 

 ent corpuscle in the blood serum. It is capable of growth 

 and assimilation of food, and to some extent of amoeboid 

 movements. The archosome itself contains three separate 

 spheres, inclusive of the centrosomes. The plasmocyte 

 possesses the following properties: organization, growth, 

 assimilation of food through phagocytosis, motion, both as 

 a whole and by the individual inner spheres, and, finally, 

 sensitiveness, shown in selecting a certain quality of food 

 (erythrocyte fragments and bacteria). 



17. The plasmocytes are derived from the red blood 

 cells and not from the leucocytes. The archosome of the 

 leucocytes does not survive, but disintegrates at the same 

 time as the balance of the leucocyte. 



18. The granosphere is the seat of phagocytosis and 

 must be considered as the digestive organ of the cell and 

 the plasmocyte, and the storehouse for accumulated food. 

 The somosphere is probably the assimilative organ of the 

 archosome and especially of the centrosomes. The hyaline 

 globules frequently found in the somosphere I consider as 

 food supply. The process of assimilation would then be as 

 follows : The food, derived from the blood serum and through 

 phagocytosis, is digested and assimilated by the grano- 

 sphere for the benefit of the plasmocytes at large. This 

 food supply when accepted by the archosome is further 

 digested by the somosphere for the special benefit of the 

 centrosomes. 



From this we may conclude that the granosphere is a con- 



Proc. Cal. Acad. Sci., 3D Ser., Zool., Vol. I. (5) March 31, 1897. 



