2 1 6 GRAF. 



without processes. The nuclear membrane is thicker, the 

 chromatin granules more crowded. 



The central canal is surrounded by a cuticular layer in which 

 the intracellular musculature, consisting of parallel rings studded 

 with granules and united by cross anastomoses, is developed. 1 



The peripheral organs are best developed in the cells of this 

 part of the nephridium. 



There is nothing new to be said with regard to the structure 

 in the terminal vesicle and the terminal canal. 



The main point of the cytological part of the paper is the 

 demonstration of true organs in the cell which develop gradually 

 under a gradually increasing stimulus. 2 



With regard to the rest of the paper, I simply mention that 

 it chiefly deals with the distribution of the pigment and with 

 the cytology and physiology of the elements connected with 

 that process. 



1 See Physiology of Excretion. 2 Ibid. 



