The cell in development and inheritance . Fig. 45. — MMosis in Actinosp/icerium. [R. Hertwig.]A. Encysted form, with resting nucleus; chromatin aggregated into large nucleolus-like bod}.B. prophase of division of the encysted form, showing chromosome-Hke bodies formed of crranules,and spindle without centrosomes. C. Earlier prophase of the first maturation division, showingextrusion of chromatic substance to form the centrosome. D. Later stage, showing- centrosomeand aster. occur without discoverable external cause ; and it is a very interestino-fact, as Klebs, Hansemann, and Galeotti have esp
The cell in development and inheritance . Fig. 45. — MMosis in Actinosp/icerium. [R. Hertwig.]A. Encysted form, with resting nucleus; chromatin aggregated into large nucleolus-like bod}.B. prophase of division of the encysted form, showing chromosome-Hke bodies formed of crranules,and spindle without centrosomes. C. Earlier prophase of the first maturation division, showingextrusion of chromatic substance to form the centrosome. D. Later stage, showing- centrosomeand aster. occur without discoverable external cause ; and it is a very interestino-fact, as Klebs, Hansemann, and Galeotti have especially pointed out,that they are of frequent occurrence in abnormal growths such ascancers and tumours. The abnormal forms of mitoses are arranged by Hansemann in twogeneral groups, as follows: (i) asymmetrical mitoses, in which thechromosomes are unequally distributed to the daughter-cells, and (2)multipolar mitoses, in which the number of centrosomes is more than 98 CELL-DIVISION two, and more than one spindle is formed. Under the f
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectcells, bookyear1902
