General principles of zoology . FIG. 91.—Stages in the fertilization of the egg of the sea-urchin. fAfter O. Hertwig.) Thesperm-nucleus (sk) with its rays in one egg is near the surface, in the other near the egg-nucleus (ek). tion completed, we here find the important fundamentalproposition that the essential feature of fertilisation consistsin the union of egg and sperm nuclei. Part Played by the Two Nuclei in many cases an abbreviation of development may takeplace, the stage of the cleavage nucleus being omitted, andthe egg and sperm nuclei, without previously uniting, pas
General principles of zoology . FIG. 91.—Stages in the fertilization of the egg of the sea-urchin. fAfter O. Hertwig.) Thesperm-nucleus (sk) with its rays in one egg is near the surface, in the other near the egg-nucleus (ek). tion completed, we here find the important fundamentalproposition that the essential feature of fertilisation consistsin the union of egg and sperm nuclei. Part Played by the Two Nuclei in many cases an abbreviation of development may takeplace, the stage of the cleavage nucleus being omitted, andthe egg and sperm nuclei, without previously uniting, passdirectly into the cleavage spindle. This fact in no wise.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1896
