. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. FIG. I. Semi-diagrammatic representation shewing the formation and history of the cross-shaped type of tetrads; a, bivalent chromatin segment as it appears in the very early prophase; b, planes of longitudinal and transverse cleavage established; c, d, later stage in evolution of prophase tetrad; e, f, tetrads as seen in early metaphase; g, tetrad in act of division, showing the manner in which the component parts glide over each other; h, early anaphase showing distortion of halves of tetrad due to their close adhesion; ;,
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. FIG. I. Semi-diagrammatic representation shewing the formation and history of the cross-shaped type of tetrads; a, bivalent chromatin segment as it appears in the very early prophase; b, planes of longitudinal and transverse cleavage established; c, d, later stage in evolution of prophase tetrad; e, f, tetrads as seen in early metaphase; g, tetrad in act of division, showing the manner in which the component parts glide over each other; h, early anaphase showing distortion of halves of tetrad due to their close adhesion; ;, daughter chromosome in metaphase of second spermatocyte. FIG. II. Corresponding stages in evolution of the clouble-V type of tetrad. I wish, however, to emphasize two points. First the points at the ends of the shorter arms of the cross-like figure (Fig. I, b, c,d) represents the point at which union occurred during synapsis. The attachment of the mantle fibers in the metaphase is not at this point as it is said to be in Syrbula by Robertson (:o8, op. cit.}, but is at the ends of the longer arms of the cross as shown in Fig. I, c,f, g. Robertson believes that the attachment of the mantle fibers. 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
