230 



it is less easily traceable iu tbe narrower portion of the nephri- 

 dial tube (fig. 6 , Nd) wbere it passes between the seta-muscles 

 (ms & ms') on its way towards the widened terminal reservoir 

 of the nephridium (fig. 7 , Nd , R). 



In the long duet by which the dorso-lateral nephridiopores are 

 connected with the reservoirs first mentioned and which , as noticed 

 above, run between the inner longitudinal and the outer circular 



