The cell in development and inheritance . vitelline membrane is, however, often formed soonafter fertilization, as in echinoderms. The most interesting featureof the plant-ovum is the fact that it often contains plastids (leuco-plasts or chromatophores) which, by their division, give rise to thoseof the embryonic cells. These sometimes have the form of typicalchromatophores containing pyrenoids, as in Volvox and many otherAlgae (Fig. 64). In the higher forms (archegoniate plants), accordingto the researches of Schmitz and Schimper, the q%% contains numer-ous minute colourless leucoplasts, whic
The cell in development and inheritance . vitelline membrane is, however, often formed soonafter fertilization, as in echinoderms. The most interesting featureof the plant-ovum is the fact that it often contains plastids (leuco-plasts or chromatophores) which, by their division, give rise to thoseof the embryonic cells. These sometimes have the form of typicalchromatophores containing pyrenoids, as in Volvox and many otherAlgae (Fig. 64). In the higher forms (archegoniate plants), accordingto the researches of Schmitz and Schimper, the q%% contains numer-ous minute colourless leucoplasts, which afterward develop intogreen chromatophores or into the starch-building amyloplasts. Thisis a point of great theoretical interest; for the researches of Schmitz,Schimper, and others have rendered it highly probable that these 134 THE GERM-CELLS plastids are persistent morphological bodies that arise only by thedivision of preexisting bodies of the same kind, and hence may betraced continuously from one generation to another through the.
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectcells, bookyear1902
