30 T. H. BURLEND, 



VIII 



4,15 \ Tubule which appears to be incomplete; it opens into 



4,16/ the lower end of the nephrotome (or into coelom?). 



4,19 1 



? Tubule with nephrostome opening into the coelom. 



4,20^ 



4,23/ Tubule with an opening into the open nephrotome or 

 4,24/ coelom and possibly related to the succeding tubule. 

 \ 4,28 — 4,32 A tubule with a nephrotomic opening in 4,29 and 

 I an indication of a nephrostome at 4,32 also. 



(In and behind this region the nephrotome is a hollow thick- 

 X I walled sac, with an opening into the duct at 4,35 and 4,42, 

 I but without any opening into the coelom. 

 The pronephric duct on this side is not present behind 7,14. 

 The origin of the duct near its posterior end is evidently due to the 

 proliferation of the adjoining somatopleuric mesoderm. 



Embryo J. 



Stained with Ehelich's Haematoxylin. Sectioned, and mounted 

 on 6 slides having 50, 51, 50, 49, 54 and 63 sections respectively. 



Body begins 1,3. 



