60 CALIFORNIA ACADEMY OF SCIENCES. [3D Ser., 



8. The plasmocytoblast is capable of development and 

 division into two, three, or more plasmocytes, which finally 

 separate from the nuclear vicinity, each one forming a free 

 and independent active plasmocyte in the blood serum. 



9. The plasmocyte undoubtedly survives in this state 

 for a considerable length of time and must take rank with 

 the other principal and active corpuscles in the blood, the 

 erythrocytes and leucocytes. 



10. The plasmocyte is capable of growth through assim- 

 ilation of food and exhibits phagocytosis. It contains the 

 same cytoplasmic zones as are found in the plasmocyto- 

 blast but has no nucleus. 



11. The determining part of the plasmocyte is the arch- 

 osome, or centrosomes with spheres, as without them the 

 plasmocyte is not formed. Imperfect plasmocytoblasts, or 

 such as do not possess an archosome, do not develop plas- 

 mocytes. 



12. The non-existence of attraction rays is probably 

 explained by the absence of a cell wall. 



13. The nucleus of the fusiform corpuscle goes quickly 

 to decay, no part of it surviving in the plasmocyte. 



14. The archosome is not merely an organ in the cell — 

 a large microsome formed for the special purpose of mitosis 

 — but constitutes a most important element of it, the very 

 center of organization, equal in importance to the nucleus 

 itself. The archosome can no more be said to originate in 

 the cytoplasm than it does in the nucleus. The only con- 

 nection the archosome has with the cytoplasm is that of 

 resting in it and of being partly nourished by it. That the 

 centrosome is at times found in the nucleus, as has been 

 shown by Brauer and Lauterborn, does not imply that it 

 originates in the nucleus, but simply that in some in- 

 stances it temporarily resides there. The archosome pos- 

 sesses the same individuality whether residing in the cyto- 

 plasm or in the nucleus. 



15. The survival of the archosome, with its phenomena 

 of growth and phagocytosis, and its general independence, 

 suggests a symbiosis between the archosome, the caryo- 



