. Animal biology. Biology; Zoology; Physiology. THE CONTINUITY OF LIFE Primordial germ cells B 245 Sperm Spermatogonia and oogonia Primary spermatocyte and primary oocyte D Secondary spermatocytes and secondary oocytes E Spermatids and egg and polocytes F Fertilization. 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 work.. Woodruff, Lorande Loss, 1879-1947. New York The Macmillan company

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RMRN5GAW–. Animal biology. Biology; Zoology; Physiology. THE CONTINUITY OF LIFE 237. 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 work.. Woodruff, Lorande Loss, 1879-1947. New York The Macmillan company

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RMRN5G5D–. Animal biology. Biology; Zoology; Physiology. THE CONTINUITY OF LIFE 241 When the chromosomes have assumed definitive form, the pre- liminary events which constitute the prophase of mitosis are. 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 work.. Woodruff, Lorande Loss, 1879-1947. New York The Macmillan company

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