. The Biological bulletin. Biology; Zoology; Marine biology. Vs mm Figure 3. Viva mutabilis. Young dzv individuals from zoospores. b, 19 days old; c, 30 days old. 1 mm c a, 12 days old; evident that dw SI individuals grow much more rapidly and, therefore, become fertile earlier than dw-individuals. The first crossings all resulted in sporophytes of the same kind as the mother sporophyte (Fig. 2). It was only after 84 plants had been tested that the crossings between the three successive individuals and the wild-type gave another result, namely, sporophytes of the wild-type. Upon the formation
. The Biological bulletin. Biology; Zoology; Marine biology. Vs mm Figure 3. Viva mutabilis. Young dzv individuals from zoospores. b, 19 days old; c, 30 days old. 1 mm c a, 12 days old; evident that dw SI individuals grow much more rapidly and, therefore, become fertile earlier than dw-individuals. The first crossings all resulted in sporophytes of the same kind as the mother sporophyte (Fig. 2). It was only after 84 plants had been tested that the crossings between the three successive individuals and the wild-type gave another result, namely, sporophytes of the wild-type. Upon the formation of zoospores eleven weeks later, they segregated into the mutant and the wild-type in the ratio 1:1. A precise count was not taken as already at the first glance into the microscope it was evident that the two types were repre- sented equally strongly. For each crossing undertaken, the gametes of the mutant partner were put to parthenogenesis. In the first 84 cases mentioned the gametes developed, as expected, mainly to germ plants of the ramified type, but also a few developed to individuals of the simple type. After the three crossings following, however, the ratio was reversed: most of the parthenogamete plants became simple whereas only a few became considerably ramified. Even if weak or no ramification accordingly must be said to be a typical character of the pure dw germ plant,. 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 Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-; Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report; HighWire Press. Lancaster, Pa. [etc. ] : Lancaster Press, inc. [etc. ]
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectb, booksubjectzoology
