191 1] Walter H. Eddy 79 



is incorrect, and that the venom merely absorbs the hemolysin. 



General conclusion. This brief review emphasizes the meagre 

 nature of our knowledge concerning the way in which lipins are 

 held and coordinated in cellular material, and emphasizes the neces- 

 sity for further work along these Hnes — especially the need for new 

 methods of attacking the problem. 



V. INTRACELLULAR PROTEINS 

 Walter H. Eddy 



To biologists in general the cell is the essential unit of living 

 matter, The biochemist is apt to think of it in terms of the mate- 

 rials he can obtain from it. He classifies them into primary and 

 secondary constituents, and investigates each as a unit of greater 

 or less interest. The morphologist thinks of the cell in terms of its 

 structures and is interested in tracing the development of these. 

 The physiologists are concerned primarily in the activity of the cells. 

 All, however, unite in general interest in the proteins and their sig- 

 nificance in the cell. 



The following tabulation shows how morphology and biochem- 

 istry meet in considering the cell proteins : 



Morphological cell units Proteins composing same. 



Cytoplasm Albumins, globulins, etc. 



Nucleoplasm Nucleoproteins. 



Cell membranes Keratin, elastin, chitin, gelatin. 



Chromatin Nucleoproteins ranging through 



nuclein to pure nucleic acids. 



True nucleoli Phosphoproteins. 



False nucleoli ("net-knots") ..Nuclein. 



Linin Phosphoprotein (synonyms : nu- 



cleoalbumin, plastin, parachro- 



matin, etc.). 



Centrosomes Phosphoproteins. 



Nuclear membrane Sometimes nuclein, sometimes 



phosphoproteins. 



Kossei, Heidenhain, Ehrlich, and others, have spent much time 

 in elucidating the relation of staining reactions to these protein con- 



