2 70 CHILD. [VOL. I. 



indicates that a certain degree of individuality exists up to and 

 perhaps beyond the point where it terminates, and this, together 

 with the length of the edge of c d, accounts for the presence of 

 two pores instead of the union of both sets of ducts in a single 

 pore. 



Between the segments d and c the furrows are very abnormal. 

 The ventral furrow is divided into two parts which overlap on 

 the surface, the one turning anteriorly, the other posteriorly. 

 The oblique portions are very shallow and do not bear inter- 

 proglottidal glands. 



The dorsal furrow is also in two parts. The one at the left 

 does not turn posteriorly, but continues as a very shallow fur- 

 row over the region corresponding to that which the ventral 

 furrows leave undivided, and finally unites with the right half. 

 This latter, however, continues to the left, beyond this point, 

 but turns anteriorly, running up into the segment and ending 

 just dorsal to the ovary. The oblique portion is shallow, like 

 the oblique portions of the ventral furrow, and bears no glands. 

 The genital organs at the left of d and e are normal, however, 

 doubtless because the growth has been normal in the regions 

 where the organs occur. Only the oblique portion of the dor- 

 sal furrow approaches the ovary, but, as has been repeatedly 

 shown, the position of the ovary is influenced only very slightly, 

 if at all, by the form of the dorsal surface. 



Figure 32. 



At the stage of development shown in the figure the genital 

 masses are becoming differentiated into the various organs. 

 The female portion is mostly distinct from the male, and the 

 strands of cells forming the ducts extend nearly or quite to the 

 edge of the body, though the pores are not distinct as yet. 

 The variation shown is a spiral in. which the furrow makes two 

 complete turns, the spiral segment bounded by it making one 

 complete turn. The spiral begins on the right in the short 

 furrow bounding a posteriorly and separating it completely 

 from the proglottid behind ; from this point it passes around 

 the body, bending forward at the right side of the upper sur- 



