. The cell in development and inheritance. Cells. 3IO SOME /'A'0/i/./â :.US OF CELL-ORCAhUZATIOX the astral rays arc thinner and stain less deeply than farther out. Brauer's account is substantially the same, thou<^h no definite "Heller Hot" was found, and the astral rays were traced directly in to the boundary of the centrosome. He added, however, two impor- tant observations, \\z. ( i ) that the central granule is visible at every period ; and (2) diiisioi of the centrosome is preceded by division of t/ie ccfitni/grann/e {Â¥\g. 148)â-an observation recently extended by Boveri to
. The cell in development and inheritance. Cells. 3IO SOME /'A'0/i/./â :.US OF CELL-ORCAhUZATIOX the astral rays arc thinner and stain less deeply than farther out. Brauer's account is substantially the same, thou<^h no definite "Heller Hot" was found, and the astral rays were traced directly in to the boundary of the centrosome. He added, however, two impor- tant observations, \\z. ( i ) that the central granule is visible at every period ; and (2) diiisioi of the centrosome is preceded by division of t/ie ccfitni/grann/e {Â¥\g. 148)â-an observation recently extended by Boveri to the division of the egg-centrosome.' Van Beneden and Neyt {'^7\ on the other hand, gave a quite different accoinit of the. Fig. 152. â Diagrams illustrating various accounts of centrosome and aster. A. Centrosome, a simple granule at the centre of the aster; ex. sperm-aster in various animals. B. "Centrosome," a sphere enclosing a central granule or centriole; ex. Brauer's account of spermatocytes of Ascaris. C Like the last, but " centrosome " surrounded by a " Heller Hof"; ex. Boveri's account of the centrosome of the Ascaris egg. D. Central granule surrounded by a radial sphere ("centrosome") bounded by a microsome-circle, and lying in a "Heller Hof"; ex. polar spindles of Thysaiiozoo)i, Van der Stricht. E. Central granule ("centrosome") sur- rounded by medullary and cortical radial zones, each bounded by a microsome-circle; ex. polar spindle of L'/iio, Lillie. F. Van Beneden's representation of aster of the Ascaris egg; like the last, but the " corpuscule central " consisting of a group of granules. G. " Centrosome," a group of granules surrounded by a "Heller Hof"; ex. the echinoderm-egg. H. "Centrosome" (central granule) surrounded by a vague larger body lying in a reticulated centrosphere; ex. Thalassema. [Griffin.] structures at the centre of the aster. The " c
Size: 2082px × 1200px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectcells, bookyear1906
