. The cell in development and inheritance. Cells. 5 pronucleus (Fig. ^2, C-H). Each animal now contains a cleavage- nucleus equally derived from both the conjugating animals, and the latter soon separate. The cleavage-nucleus in each divides three times successively, and of the eight resulting bodies four become macronuclei and four micronuclei (Fig. 82, H-K). By two suc- ceeding fissions the four macronuclei are then distributed, one to each of the four resulting individuals. In some other species the micro- nuclei are equally dis- tributed in like man- ner, but in /'. cauda- tuui the process
. The cell in development and inheritance. Cells. 5 pronucleus (Fig. ^2, C-H). Each animal now contains a cleavage- nucleus equally derived from both the conjugating animals, and the latter soon separate. The cleavage-nucleus in each divides three times successively, and of the eight resulting bodies four become macronuclei and four micronuclei (Fig. 82, H-K). By two suc- ceeding fissions the four macronuclei are then distributed, one to each of the four resulting individuals. In some other species the micro- nuclei are equally dis- tributed in like man- ner, but in /'. cauda- tuui the process is more complicated, since three of them degenerate, and the fourth divides twice to produce four new micronuclei. In either case at the close of the process each of the conju- gating individuals has given rise to four descendants, each containing a macro- nucleus and micro- nucleus derived from the cleavage-nucleus. From this time for- ward fission follows fission in the usual manner, both nuclei dividing at each fis- sion, until, after many generations, conjuga-. 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
Size: 1584px × 1577px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectcells, bookyear1896
