. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. A NEW SPECIES OF CHLAMYDOMONAS and within 24 hours a zygote is formed. If the gametes are of equal size a spherical zygote results (Fig. 13) ; if the gametes are of unequal size, a "pear- shaped" zygote is formed, resulting possibly from the denser consistency of the larger cell (Fig. 14). A thick wall is secreted around the zygote. Both pyrenoids and nuclei are visible in the zygotes for as long as 48 hours (Fig. 12). In some. FIGURES 15-24. Chlatnydonwnas inicrolialopliila. FIGURE IS, six-month-old zygote in me-
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. A NEW SPECIES OF CHLAMYDOMONAS and within 24 hours a zygote is formed. If the gametes are of equal size a spherical zygote results (Fig. 13) ; if the gametes are of unequal size, a "pear- shaped" zygote is formed, resulting possibly from the denser consistency of the larger cell (Fig. 14). A thick wall is secreted around the zygote. Both pyrenoids and nuclei are visible in the zygotes for as long as 48 hours (Fig. 12). In some. FIGURES 15-24. Chlatnydonwnas inicrolialopliila. FIGURE IS, six-month-old zygote in me- dian optical section with large oil droplets concentrated at the periphery. FIGURES 16-18, zygote germination. FIGURE 19, early prophase of nuclear division showing some of the chromatin bodies before condensation into chromosomes, pyrenoid elongating. FIGURE 20, pyrenoid has divided and cytokinesis is being initiated in the region of the nucleus; the latter in late pro- phase showing 16 chromosomes. FIGURE 21, anaphase stage with approximately 16 chromo- somes moving toward the opposite poles; the pyrenoid has not divided nor has cytokinesis been initiated. FIGURE 22, first cleavage is completed, and nuclei are in prophase stage for second division; pyrenoid in one of the cells is elongating. FIGURE 23, second cleavage, pyre- noids divided, and chromosomes at metaphase. FIGURE 24, division of pyrenoids preceding second cleavage. instances, the pyrenoids were visible after several weeks. The zygote enlarges to as much as 22 /j. in diameter as it matures. Dormant zygotes several weeks old accumulate droplets of colorless oil in the periphery, with the chlorophyll con- centrated in the center (Figs. 15 and 30). With increasing age the oil droplets enlarge. Very large, reddish-orange colored oil droplets, as confirmed by Sudan III, were observed in dormant zygotes 6 months old. To effect germination, zygotes which had dried on agar, under illumination. Please note that these image
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
