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KAKM NARAYAN BAHL 



have been left over from the original nephridial masses, or 

 whether they arise from epidermal cells that become nephridial 

 at the time and migrate inwards, I cannot be sure. On 



Text-fig. 7. 



ft A ti % !§ '^ ^ 



sec.i.n. 



Portion of a whole mount of an embryo about to hatch out of the 

 cocoon, showing the fully-formed primarj' septal nephridia 

 and the primary and secondary integumentarj' nephridia. s.n., 

 septal nephridia ; p.i.n., primary integumentary' nephiidia ; 

 sec.i.n., secondary integumentary nephridia ; n.c, nerve-cord. 



examining Text-fig. 4 it would seem as if the nephridial sub- 

 stance (cells potentially nephridial) is spread over the whole 

 of the body-wall, and any part of it might become active and 

 form a nephridium, and hence the appearance of nephridia 

 at all sorts of places on the body-wall. If that be the case, 

 and if, as shown in fig. 8, nephridial cells extend on each side 

 of the definite nephridial rudiments, we probably get these 



