. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. FIGURE 2. Organ Anlai/en of embryo at about stage 21. Gl., gill; an., anal papilla ; ot., otocyst; ff., funnel folds; yk., yolk sac; sh., shell gland; opt., optic ganglion ; mo., mouth ; sal, salivary pit. STAGE 1. STAGE 2. STAGE 3. STAGE 4. STAGE 5. STAGE 6. STAGE 7. STAGE 8. STAGE 9. STAGE 10. STAGE 11. STAGE 12. STAGE 13. STAGE 14. STAGE 15. Fertilized but lacking polar bodies. Ooplasmic streaming occur- ring to form the blastodisc. First maturation division. Blastodisc quite evident. Second maturation division. Slight in
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. FIGURE 2. Organ Anlai/en of embryo at about stage 21. Gl., gill; an., anal papilla ; ot., otocyst; ff., funnel folds; yk., yolk sac; sh., shell gland; opt., optic ganglion ; mo., mouth ; sal, salivary pit. STAGE 1. STAGE 2. STAGE 3. STAGE 4. STAGE 5. STAGE 6. STAGE 7. STAGE 8. STAGE 9. STAGE 10. STAGE 11. STAGE 12. STAGE 13. STAGE 14. STAGE 15. Fertilized but lacking polar bodies. Ooplasmic streaming occur- ring to form the blastodisc. First maturation division. Blastodisc quite evident. Second maturation division. Slight increase in the size of the blastodisc. First cleavage along the plane of symmetry. Second cleavage occurs asymmetrically. Embryonic anterior and posterior are evident. Third cleavage. Division is unequal and asynchronous. Fourth cleavage. Division is unequal and asynchronous. Fifth cleavage. Blastoderm often asymmetrical and somewhat irregular. About 32 cells. Sixth cleavage. About 64 cells. Embryonic anterior and posterior no longer distinguishable. Formation of a second layer of cells to form a papilla of yolk in the center of the blastoderm. Yolk papilla flattened. Blastoderm spreading by marginal division. Blastocones can be distinguished but not easily in this species. Mlastodcrm covers about one-third of the egg. Blastocones no longer evident. About two-fifths of the egg cellulated. About three-fifths of the egg 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 Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass. : Marine Biological Laboratory
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
