. The cell; outlines of general anatomy and physiology. hese, abright central corpuscle (centrosome),surrounded by a radiation sphere, mayvery frequently be seen. This wasobserved and depicted by R. Hertwig,and has recently been more clotely in-vestigated by Brandt. The latter ob-server was able to follow how, at thetime of reproduction, the centrosomerwhich appears to me to correspondwith the body of that name in plantand animal cells, betakes itself to thesurface of the internal vesicle, drawingthe radiation sphere after it. Here,after passing through the nuclearmembrane, it enters into the
. The cell; outlines of general anatomy and physiology. hese, abright central corpuscle (centrosome),surrounded by a radiation sphere, mayvery frequently be seen. This wasobserved and depicted by R. Hertwig,and has recently been more clotely in-vestigated by Brandt. The latter ob-server was able to follow how, at thetime of reproduction, the centrosomerwhich appears to me to correspondwith the body of that name in plantand animal cells, betakes itself to thesurface of the internal vesicle, drawingthe radiation sphere after it. Here,after passing through the nuclearmembrane, it enters into the surround-ing protoplasm of the central capsule ;however, as yet nothing has been re-ported as to its further fate. About this time a large number ofsmall nuclei make their appearanceoutside of the internal vesicle, beingsituated in the protoplasm of the cen-tral capsule, which originally was quitefree from nuclei; these function ascentres around which nucleated zoospores develop, whose numberfinally may amount to some hundreds of thousands. Meanwhile,. Fig. 105.—A small portion of asection through a great vesicularnucleus, the so-called internalvesicle of Thalassicolla nucleatawith funicular internal bodies(nuclear bodies) which radiatefrom a common point. (R. Hert-wig, PI. V., Fig. 7.) THE VITAL PHENOMENA OF THE CELL 213 the internal vesicle begins to shrink up and loses its nuclei,which pass into the protoplasm outside. Finally it is quite dis-solved. Brandt has observed that this nuclear multiplicationvaries according to whether isospores or anisospores are formed. From the whole process R. Hertwig and Brandt draw thefollowing conclusion, which is certainly correct: that the nucleiwhich function in the formation of zoospores, and which occur inthe central capsule, at first but sparsely, but which graduallyincrease in number, are derived from the substance of the internalvesicle (nuclear corpuscles). This explanation, remarks , leads me to adopt a theory of nuclear
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