. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 348 A. P. MATHEW 1. KEY TO LETTERING A, large follicle with blastoderm surrounded by chorion. Al, egg with blastoderm sinking into the ovarian tube. A2, "empty chorion" from which the embryonic rudiment has passed out. Develops into corpus luteum 2, forming the embryonic feeding mechanism. B, small follicles with eggs (earlier). C, cells at the base of the follicle become glandular corpus luteum 1. D, the cast off chorion and stalk—corpus luteum 3. E, embryo. Mg, midgut of the embryo. St, stalk of the feeding mecha
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 348 A. P. MATHEW 1. KEY TO LETTERING A, large follicle with blastoderm surrounded by chorion. Al, egg with blastoderm sinking into the ovarian tube. A2, "empty chorion" from which the embryonic rudiment has passed out. Develops into corpus luteum 2, forming the embryonic feeding mechanism. B, small follicles with eggs (earlier). C, cells at the base of the follicle become glandular corpus luteum 1. D, the cast off chorion and stalk—corpus luteum 3. E, embryo. Mg, midgut of the embryo. St, stalk of the feeding mechanism connected with the embryonic gut. FIGURE 1. Part of the ovarian tube (early) bearing follicles enclosing blastoderms or eggs. FIGURE 2. A follicle with blastoderm sinking into the ovarian tube (Al), causing the part of the ovarian tube to bulge a little. At the site of the insinking (C, C) the outer cells begin to enlarge and become glandular. FIGURE 3. The embryonic rudiment (E) is pushed into the ovarian tube from the ruptured "chorion" (A2), which is at the same time pushed upwards, everting the invaginated outer layer at the site of the insinking of the egg. The cells of this portion (C) have now become enlarged and glandular. At this stage they form button-like thickenings on the swollen parts of the ovarian tube in which are the developing embryos. FIGURE 4. The upward movement of the chorion (A2) continues. It pushes itself out of the inner layer and projects out, covered over by the everted glandular cells of the follicle (C).. 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 Cla
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
