. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. No. 5.] THE CESTODE MONIEZIA EXPANSA. 231 nearer together than at the left, where the separation of the seg- ments is complete and normal. It appears from the arrangement of the organs at the right that the two segments c and d do pre- serve a certain degree of individuality in the region beyond the end of the partial furrows, for if this were not the case we should expect to find only one pore instead of two, a condition which does frequently occur. The position of the ovary and vitel- larium at the right of d is peculiar.
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. No. 5.] THE CESTODE MONIEZIA EXPANSA. 231 nearer together than at the left, where the separation of the seg- ments is complete and normal. It appears from the arrangement of the organs at the right that the two segments c and d do pre- serve a certain degree of individuality in the region beyond the end of the partial furrows, for if this were not the case we should expect to find only one pore instead of two, a condition which does frequently occur. The position of the ovary and vitel- larium at the right of d is peculiar. The ducts, instead of bending posteriorly, extend straight inward, and the ovary lies nearer the middle of the segment than the others. This posi- tion is apparently due to the form relations here. The distal portions of the two sets of organs at the right of c and d are approximated, but the partial furrows between c and d extend to the region of the ovaries, and d is slightly shorter in this region than c, so that the ovary and vitellarium in d take the position in which they can attain most nearly their normal development. Inter-proglottidal glands occur in the partial furrows as well as in those which are complete. Figure 1$. This figure shows a case of partial division in which the partial furrows are nearly complete. The segments are rather old, the ovaries and ducts being in process of degeneration and the uterus containing embryos (not drawn in figure). At the left side the segments are normally bounded, and the genital organs are apparently normal. At the right the partial. FIG. 15. furrows end before reaching the edge, and two sets of organs occur, opening into a common pore. The partial furrows extend so nearly to the edge that in the ovarian region the two segments. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble th
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
