Licence: Public Domain Mark
Credit: Elements of histology / by E. Klein. Source: Wellcome Collection.
Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.
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![CIu-ip. I.] earlier phases—6.^7., in the phase of the spireme. When the nucleus divides into two or three oi' more nuclei without the cell protoplasm also undergoing division, a cell with two, three, or more nuclei is the result. Multiplication of the nucleus by budding and direct fission has also been observed, but it is quite [)0ssible that this process is only as a sort of imperfect and abnormal karyomitosis. This mode probably plays a more important part than the typical karyomitosis, whenever a rapid mul- tiplication'and reproduction is necessary. Thus, for instance, while in the epithelium cells covering the anterior surface of the normal cornea of the newt and frog, here and there a nucleus can be seen which shows the process of typical karyomitosis, such forms cannot be found in cases of rapid regeneration of that e[)ithe]ium. For example, after removing the whole thickness of the anterior epithelium from the middle part of the cornea, a rapid multiplication of the epi- thelium cells takes place, starting from those imme- diately around the defect ; in consequence of this, in two to three days the defect becomes again quite covered with the new epithelium. Now, ex- amining the epithelium cells at the margin of the defect, as well as those gradually pushed over and covering the defect, none of the nuclei are found in any of the phases of typical karyomitosis ; while a few days later, after the defect is covered by the new epithelium, there is no difficulty in finding nuclei in one or another phase of the typical karyomitosis.](https://iiif.wellcomecollection.org/image/b24757238_0031.jp2/full/800%2C/0/default.jpg)
