262 CHILD. [VOL. I. 



The lower surface shows no corresponding furrow. The length 

 of the proglottid at this side is somewhat greater than, but not 

 double, the normal length, i.e., it is not as long as two fused 

 proglottids of the same age. Two groups of cells, the 

 <( Anlagen," of the reproductive organs or " genital masses," 

 appear upon this side, however, as would be the case if the 

 short partial furrow were complete. The furrow itself indi- 

 cates the imperfectly double character of the segment, and the 

 two genital masses show this still more clearly. At the left a 

 is only half as long as at the right and possesses only a single 

 genital mass. The partial segment b is completely separated 

 from a both on the upper and lower surface, but is seen to be 



connected with c on the lower surface. 

 The furrow separating b from a runs 

 inward and somewhat anteriorly from 

 the left edge for about one-third the 

 width of the body, then turns and ex- 

 tends outward and anteriorly until it 



FIG. 24. r . , 



joins the complete furrow in front. 



Thus the small piece b is completely marked off on the upper 

 surface, and though its edge at the left side is of normal length, 

 it narrows to a rounded end. On the lower surface the rela- 

 tions are different, for the partial furrow between b and c on 

 this surface ends free, while the complete furrow separating a 

 and c at the right bends so as to pass posteriorly to b at the 

 left and connects at the left edge with the furrow between a 

 and b. The partial segment b is thus a short spiral, making 

 less than half a turn. Notwithstanding its small size, it shows 

 a genital mass as large and distinct as any at this stage. 



Fiure 2. 





Here two examples of partial division and a short spiral 

 occur. Upon the upper surface the two partial proglottids a 

 and b are incompletely separated, the partial furrow on the left 

 side being longer than that on the right. The partial furrows at 

 the right correspond exactly on the two surfaces, both ending 

 free. The partial furrow on the upper surface at the left forms 



