Observation on the Nephridia of tbe Alciopinae. 



187 



(Textfig. A). The coelomostome is much shorter than the nephridium, 

 so that it opens into the latter near its anterior extremity (Fig. 8). 

 That portion of the nephridial canal which lies behind the point 

 of junction becomes modified to fulfill its new function (cp. figures 6 

 and 7). The lnmen becomes wider, the wall thinner, and the cilia. 

 wich formerly were few and very long-; now become shorter and 

 much more nnmeroas. In front of the point of junction the nephridial 

 canal retains its original strukture. The various stages in the 

 fusion of the two organs can be well seen for instance in Asterope 

 Candida. Fig. 11 shows that the dividing wall becomes thinned 



PP-. 



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Fig. A. 



Diagram of 3 stages in the development 

 of the nephromixium in Alciope. 



Fig. B. 



Diagram of 4 diöerent conditions of 

 the coelomostome and nephridium. 



