No. 6.] THE CESTODE MONIEZIA EXPAA^.l. 279 



The difference in the relations in these two cases is un- 

 doubtedly clue to the difference in depth of the two furrows. 

 In the case of d the furrow is deep enough either to interrupt 

 the course of the ducts or else to produce conditions approach- 

 ing those at the edge of the body, and consequently the pore 

 forms here instead of at the edge. The ducts are slightly 

 shorter than the normal, but the inner portions of the organs 

 show a perfectly normal arrangement. 



2. Other Abnormalities. 



Under this head are included a few cases of abnormalities 

 of a different nature from those previously described. Two of 

 these (Figs. 38 and 39) are cases of lateral duplication of the 

 genital organs, and the other two (Figs. 40 and 41) are cases 

 of alteration in position of the genital organs. 



Figure j8. 



The figure, a view from the ventral side, shows a number of 

 abnormalities. Between the segments a and b the furrows are 

 normal except near the right edge, where both curve posteri- 

 orly. On the ventral surface the furrow ends before reaching 

 the edge, while dorsally it continues to the edge. The inner 

 portions of the genital organs are normal, and the ducts 

 extend in the normal direction toward the edge, but do not 

 reach it. The pore lies on the curved dorsal furrow a short 

 distance from the edge of the body, i.e., on the dorsal surface. 

 The terminal portions of the ducts are entirely normal in 

 structure. Thus the abnormal edge formed by the curved 

 furrow affords conditions which allow a normal pore and ter- 

 minal organs to appear and so resembles closely the segment 

 d in Fig. 37, except that there the furrow between c and d 

 turns anteriorly instead of posteriorly. At the left of a the 

 form of the segment and the organs are normal. 



The segments b and c are incompletely separated on the 

 ventral surface, and c is a spiral in consequence of the peculiar 

 curve of the ventral furrow separating the parts c and d. On 



