. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 156 J. CHARLES CHEVERIE AND W. GARDNER LYNN the average height being microns (Fig. 2). The squamous cells contain little cytoplasm, and their flattened, dark-staining nuclei occupy most of the cell. The cuboidal epithelial cells have round, usually basally located, nuclei and a small amount of slightly basophilic cytoplasm. No colloid droplets or vacuoles i V*v #&• f *lfc*> *'*» :'. FIGURE 1. Section through thyroid region of an untreated control kept at room tempera- ture (21° C.) for 30 days, then at 15° C. for
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 156 J. CHARLES CHEVERIE AND W. GARDNER LYNN the average height being microns (Fig. 2). The squamous cells contain little cytoplasm, and their flattened, dark-staining nuclei occupy most of the cell. The cuboidal epithelial cells have round, usually basally located, nuclei and a small amount of slightly basophilic cytoplasm. No colloid droplets or vacuoles i V*v #&• f *lfc*> *'*» :'. FIGURE 1. Section through thyroid region of an untreated control kept at room tempera- ture (21° C.) for 30 days, then at 15° C. for an acclimation period of 60 days. SO X. FIGURE 2. A single thyroid follicle from the specimen shown in Figure 1. 485 X. FIGURE 3. Section through thyroid region of a fish kept in thiourea throughout a preacclimation period of 30 days at 21° C. and an acclimation period of 60 days at 15° C. 50 X. FIGURE 4. A single thyroid follicle from the specimen shown in Figure 3. 485 X. were observed in any of the follicular cells of the control thyroids. Except for a few of the small, more active follicles, the follicular lumina are large and filled with acidophilic, homogeneous, or granulated, non-vacuolated colloid. Examination of the thyroids of thiourea-treated fish reveals a histological picture quite different from that of the controls (Fig. 3). A great increase in the number and size of follicles has occurred so that the follicles are more compactly arranged and occupy a large portion of the sub-pharyngeal region. The average number of follicles found in a representative cross-section through the thyroid region of experimental fish is 25. The follicular epithelium is columnar and. 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 the original Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Labo
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
