THE NEPHRIDIOPORES IN THE 

 EARTHWORM. 



BY 



A. A. W. HUBRECHT. 



With Platc XII. 



In looking through a considerable series of mounted transverse 

 sections , some of Lumbricus , others of Allolobophora , which had 

 been freshly prepared for the practical class and had been put 

 in the hands of the students , I was a few weeks ago surprised 

 to find a definite opening of a tubular duet penetrating the inte- 

 gumeut about half way between the upper pair of setae and the 

 dorsal pore. 



An examination of all the available sections, afterwards com- 

 pleted by the comparison of an unbroken series of thicker ones 

 through 28 consecutive segments of the body, convinced me that 

 in very many segments similar openings are found , it bsing 

 however impossible to deterraine any regularity in the intervals 

 at which they occur. It was moreover soon settled that these pores 

 are induhitahle nephridiopores ^ that tlie, duet connecting them toith 

 their nephridium tahes its course between the longitiidinal and the 

 circular muscular layer and that the nephridia , thus connected 

 with the exterior, have no nephridial ducts (pores) just above the 

 second seta. It is the position last mentioned which we find re- 

 corded in the most recent literature on the earthworm, notably in the 

 very valuable and numerous contributions to the subject by Benham 

 and Beddard. Neither of them alludes to the variability in the 



