play a central role in the activities of the cell, and 

 that it must be of great importance in the life and ac- 

 tivities of the cell as a whole. Moreover, when the nu- 

 cleus does not occupy a central position, the ex-centric 

 position which it does occupy nay also be of significance. 

 In basement membranes and other epithelial cells of higher 

 organisms the nucleus is found toward the side of the cell 

 which is closest to the blood supply, and this, together 

 with the fact that in other cells the nucleus may be seen 

 in close proximity to, or even engulfing nutritive mater- 

 ial, leads to the conclusion that the nucleus must play an 

 important role in the nutrition of the cell. The careful 

 provision which is made for the equal division of the nu- 

 cleus, and apparently for even parts of the nucleus, when 

 the cell divides: the complex but exact changes v/hich the 

 nucleus undergoes in preparation for reproduction; the care- 

 ful allotment of certain nuclear material from each parent 

 for the formation of the new individual, and the subsequent 

 union of this nuclear material from each side, all go to 

 show that the nucleus is important in the properties and 

 characteristics, the individuality, and even the existence 

 of the cell. Nature has also furnished us, in the case of 

 the red blood corpuscle, with the interesting experiment 

 of a cell without a nucleus, and we know that its life is 



(7) 



