. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. REGENERATION IN TUBULARIA CROCEA. 295. FIG. 4. branching stems a short piece of a branch or of a stem regener- ates as does an isolated short piece, /. e., the region of the ten- tacle anlagen is reduced and the rate of development of a hydranth is much slower than that of a hydranth from the cut end of a long piece of stem. Both of these factors may help to bring about the delay in the development of a hydranth from the oral end of the shorter piece in all of these experiments with branching stems in which there is a marked
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. REGENERATION IN TUBULARIA CROCEA. 295. FIG. 4. branching stems a short piece of a branch or of a stem regener- ates as does an isolated short piece, /. e., the region of the ten- tacle anlagen is reduced and the rate of development of a hydranth is much slower than that of a hydranth from the cut end of a long piece of stem. Both of these factors may help to bring about the delay in the development of a hydranth from the oral end of the shorter piece in all of these experiments with branching stems in which there is a marked difference in the length of the stem and of the branch. Series Seventeen branching stems from different colonies were cut so that the anterior portion of the stem above the place of union with the branch was only about i mm. in length, while the length of the branch varied in different cases from 8—25 mm. (Fig. 4). Two days after the opera- tion, hydranths had developed at the cut ends of thirteen branches, and well developed tentacle anlagen were found at the oral ends of the other four branches. No hydranths were found at this time at the oral end of any of the stems, and tentacle anlagen were only faintly defined in some few cases. On the next day, hydranths had developed at the distal end of all of the branches, but only five stems bore hydranths at the oral end. In this set of experiments the development of a hydranth took place more rapidly from the cut end of the lone branch than from the oral end of o the main stem. Series j. - - Twelve experiments were made in which the anterior end of the stem and the distal end of the branch were cut off so that the length of the branch and of the stem above the place of union was practically the same, varying in different cases. 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 resembl
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
