. Fresh-water biology. Freshwater biology. 87 (84, 85, 86) Colony spherical, of 8 ori6, 32 or 64 cells evenly scattered near the surface of a gelatinous sphere. . Evdorina Ehrenberg. Cells spherical or oval, with two cilia and a pigment spot. Chromatophore single, parietal. Vegetative re- production by repeated division, forming at first a plate-like daughter colony, which later becomes spher- ical. Sexual reproduction by a pear-shaped anthero- zoid and a spherical oosphere. The cells lie at the surface of the gelatinous sphere and the ciha project at right angles to the surface. All of the ve
. Fresh-water biology. Freshwater biology. 87 (84, 85, 86) Colony spherical, of 8 ori6, 32 or 64 cells evenly scattered near the surface of a gelatinous sphere. . Evdorina Ehrenberg. Cells spherical or oval, with two cilia and a pigment spot. Chromatophore single, parietal. Vegetative re- production by repeated division, forming at first a plate-like daughter colony, which later becomes spher- ical. Sexual reproduction by a pear-shaped anthero- zoid and a spherical oosphere. The cells lie at the surface of the gelatinous sphere and the ciha project at right angles to the surface. All of the vegetative cells may become transformed into oogonia and antheridia; in each of the latter 64 anther- ozoids are formed. The ripe oospores are brownish with a smooth external membrane. The habitats of Eudorina are ponds, ditches, and lakes. Fig. 152. Eudorina ekgans Ehrenberg. (After Stein.). 88 (80, 83) Colony a larger gelatinous sphere with a very large number of minute cells at the surface Volvox Linnaeus. CtUs very small, round or pear-shaped, connected by protoplasmic filaments, each with a pair of cilia, a single chromatophore and two or more contractile vacuoles; reproduction sexual and asexual; in the latter certain cells (parthenogonidia) within the sphere enlarge and through divisions give rise to a new colony. Sexual reproduction occurs by the union of a fusiform antherozoid and oosphere; oospore spherical, with red contents and a spiny membrane. 89 (69) Colonies not motile in the vegetative condition 90 90 (95> i3i> 17s) Cells in colonies, generally sessile and enclosed in a definite gelatinous envelop, or borne on gelatinous stalks. Reproduction asexual by zoospores, or sexual by isogametes. Family Teirasporaceae . 91 91 (94) Cells biciliate, at the surface of an inflated, attached colony. Cilia external and free 92. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appear
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectfreshwa, bookyear1918
