2QO CHILD. 



much smaller than the one posterior to it and without any 

 ducts opening into it. Apparently the greater length of this 

 edge has afforded space, 'as it were, for the formation of another 

 pore, but the ducts connecting with it fail to appear. This 

 case, like a number of others, shows that the pore may be 

 wholly unconnected with the other organs, but that its formation 

 is doubtless due to the general conditions that lead to the 

 formation of the other portions of the set, even though the 

 two parts do not unite. 



Figure 41. 



This case is very similar to the one shown in Fig. 40. The 

 development is so far advanced that it is impossible to deter- 

 mine with certainty whether the division of the ducts is as 

 complete as in that case. The cell-masses at the right repre- 

 senting the two ovaries and vitellaria appear about equal in 

 size, and there are indications that they were connected with 

 the single duct leading to the pore. It is impossible to deter- 

 mine whether the vas deferens divides or not. 







HULL ZOOLOGICAL LABORATORY, 



UNIVERSITY OF CHICAGO, 



May, 1900. 



