No. 3.] THE DISCODRILID NEPHRIDIUM. 369 



spreading of the growing tubules, are indicated in Benham's 

 figure of the nephridial blood supply of Lumbricus, but I 

 have been unable to follow the suggestion up comparatively. 



We conclude as one result of the foregoing study that the 

 nephridial characters, as is true of so many other structures, 

 point to an oligochaetous alliance of the Discodrilidae ; while at 

 the same time the importance of predominating chlorogogen 

 on the one hand or direct nephridial excretion on the other, 

 as a factor influencing the arrangement of the tubules, is 

 indicated. 



