Observation on the Nephridia of the Alciopinae. 189 



nephridium. The coelomostome is therefore developed early, and 

 retains its activity throughout lue. Now if the coelomostome of 

 Alciope remained arrested in development at about the stage repre- 

 sented in Fig. 3, a condition would be presented almost exactly 

 like that which persists in Glycera. 



Merton College, Oxford, July 21, 1911. 



