. The cell in development and inheritance. Cells. 184 REDUCTION OF THE CHROMOSOMES " ids," the latter being idcntiiied with the visible chromomeres or chromatin-granules. The ids finally are associated in linear groups to form the " idants " or chromosomes. Since the biophores differ qualitatively, it follows that the same must be true of the higher units. Fig. 92. — Reduction in the of Ascarh megalocephala, var. bivalens. [Brauer.] ^ A-G. Successive stages in the division of the primary spermatocyte. The original reticuhmi undergoes a very early division o
. The cell in development and inheritance. Cells. 184 REDUCTION OF THE CHROMOSOMES " ids," the latter being idcntiiied with the visible chromomeres or chromatin-granules. The ids finally are associated in linear groups to form the " idants " or chromosomes. Since the biophores differ qualitatively, it follows that the same must be true of the higher units. Fig. 92. — Reduction in the of Ascarh megalocephala, var. bivalens. [Brauer.] ^ A-G. Successive stages in the division of the primary spermatocyte. The original reticuhmi undergoes a very early division of the chromatin-granules which then form a doubly split spireme- tliread, D. This shortens (C), and breaks in two to form the two tetrads {D in profile, E viewed endw ise). F. G. H. First division to form two secondary spermatocytes, each receiving two dyads. /. Secondary spermatocyte. J. K. The same dividing. L. Two resulting spermatids, each with two single chromosomes and a centrosonie. formed by their aggregation. Hence each chromosome has a dis- tinct and definite character of its own, representing a particular group of hereditary qualities. From this it follows that the number of 1 For division of the spermatogonia see Pig. 39 ; for the corresponding phenomena in var. iiiiii'alens see Fig. 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 Wilson, Edmund B. (Edmund Beecher), 1856-1939. New York : The Macmillan company
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectcells, bookyear1896
