. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 128 !•!.( IRENCE MARIE S( < 'IT terior to the center l" the egg hut in the midline. The disparity in si/c of the lirst two hlastoiueres in .\niaroeciiiin indicates that the meeting of male and female pronuclei is eTfecU'd not onlv in the ])osterior region of the egg hut also to the right side- of the niidline (Fig. 1,I>; 2, A). In Amaroecium. therefore, there is a double eccentricity of the nucleus, posterior and to the right o! the- main axis of the egg. In all the sections of .\maroecium e'ggs examined t
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 128 !•!.( IRENCE MARIE S( < 'IT terior to the center l" the egg hut in the midline. The disparity in si/c of the lirst two hlastoiueres in .\niaroeciiiin indicates that the meeting of male and female pronuclei is eTfecU'd not onlv in the ])osterior region of the egg hut also to the right side- of the niidline (Fig. 1,I>; 2, A). In Amaroecium. therefore, there is a double eccentricity of the nucleus, posterior and to the right o! the- main axis of the egg. In all the sections of .\maroecium e'ggs examined the polar bodies lies eccentric- ally with respect to the main mass of yolk ( Fig. 1,A). By assuming that the germinal vesicle always lies to the right of the apex of the elliptical egg and also that the sperm penetrates on the same side it is possible to explain the lateral eccentric- ity of the zygote nucleus to the right of the median axis; this, in turn, explains the constant inequality in size of the first two blastomere>. The- second division also is meridional and at right angles to the first, thus di- viding the egg into two anterior and two posterior blastomeres. The posterior. 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
