No. 5.] THE CESTODE MONIEZIA EXPANSA. 241 



pores at the left of the figure. The existence of this line of 

 depression indicates, I believe, that f and g are really more or 

 less distinct segments, even on the left, where no true furrow 

 occurs. At the right g is as long as f, but is shorter at the left, 

 and the furrows bounding it anteriorly are abnormal, for they 

 are not transverse but extend from each edge somewhat posteri- 

 orly, thus making g very narrow just to trie-left of the middle. 

 At the right the genital organs in f and g are normal and nor- 

 mally placed. At the left the organs in f are situated a little 

 anterior to their normal position. We find, however,, a second 

 partial set of organs anterior to the first and showing relations 

 almost identical with the rudimentary organs in b in Figs. 10, 16, 

 and 17. The inner portion of the vas deferens appears, and just 

 posterior to it lie small groups of cells which apparently rep- 

 resent a portion of the female organs. These parts are, however, 

 entirely unconnected with the cirrus and pore, which are of normal 

 size and appearance. Here again the inner and the outer por- 

 tions have developed independently of each other, and the con- 

 necting ducts are absent. This case differs from those in Figs. 

 1 6 and 17, and resembles that in Fig. 10, b, in that a portion of 

 the female organs appears here. In Figs. 16, b, and 17, b, a 

 distinct furrow occurs on the dorsal side, but there are none 

 ventrally ; this condition indicating a more complete separation 

 on the dorsal side than on the ventral, while in Fig. 10, b, as in 

 this case, distinct furrows are absent on both sides in the imme- 

 diate region concerned. Probably portions of both female and 

 male organs occur in these cases, because the degree of separa- 

 tion, though slight, is the same on both sides. The incomplete- 

 ness of the organs is doubtless due here, as in the other cases, 

 to the small size of the segment. 



The inter-proglottidal glands appear on all the furrows which 

 lie within the zone of their formation. In the furrows between 

 /"and^-, however, they are found only near the right side. The 

 terminal portions of the furrows are shallow, and thus apparently 

 insufficient to cause the glands to appear. 



The region from which this figure was taken is not exception- 

 ally abnormal, but was selected because it presents a number of 

 different kinds of abnormalities near together. 



