. Carnegie Institution of Washington publication. S Papers from the Marine Biological Laboratory at Tortugas. complete dispersal of the definite and sharply contoured resulting bodies of the full-grown nucleus. In Asterias forbesii germinal vesicles were occa- sionally found in which were scattered as many as fifty or more small chro- matic masses. These were interpreted as abnormalities or the result of degeneration. But in this case the bodies were always larger or smaller globes and were found only in the younger eggs. Nor could the nucleolus ever be seen as a whole to break up into such. T
. Carnegie Institution of Washington publication. S Papers from the Marine Biological Laboratory at Tortugas. complete dispersal of the definite and sharply contoured resulting bodies of the full-grown nucleus. In Asterias forbesii germinal vesicles were occa- sionally found in which were scattered as many as fifty or more small chro- matic masses. These were interpreted as abnormalities or the result of degeneration. But in this case the bodies were always larger or smaller globes and were found only in the younger eggs. Nor could the nucleolus ever be seen as a whole to break up into such. The striking thing about Ednnaster is the change of these elements from a globular form to definitely four-lobed bodies. The case seems to be very clear for Echinaster crassispina that here the chromosomes arise exclusively from the nucleolus, the latter not even leaving a plastin remnant behind. The function of the germinal spot here seems to be wholly that of a storehouse of chromatin for the chromosomes, the latter being apparently, at least during the early history of the growth-period, compacted into one solid homogeneous mass or chromatin nucleolus, and their separate individuality merged into one common chromatic whole. It. 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 Carnegie Institution of Washington. Washington, Carnegie Institution of Washington
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