. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. IllSTORIKS OF Till-: ROTIKKk LFA'ANK 347 fertilized they produce, instead of the small, haploid, male-producing eggs, larger, dark eggs with a thick, horny shell. Such an egg has, of course, the diploid number of chromosomes. It remains unhatched for some time, and then produces a parthenogenetic or amictic female, CD. FIG. 1. Diagram showing the alternation of sexual and non-sexual generations in a bisexual rotifer, such as Lecane inermis. The most common type of individual, the non-sexual "amictic" female (
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. IllSTORIKS OF Till-: ROTIKKk LFA'ANK 347 fertilized they produce, instead of the small, haploid, male-producing eggs, larger, dark eggs with a thick, horny shell. Such an egg has, of course, the diploid number of chromosomes. It remains unhatched for some time, and then produces a parthenogenetic or amictic female, CD. FIG. 1. Diagram showing the alternation of sexual and non-sexual generations in a bisexual rotifer, such as Lecane inermis. The most common type of individual, the non-sexual "amictic" female (A), reproduces exclusively by diploid partheno- genesis. Its eggs (/) develop invariably into females, which are usually amictic, so that multiplication by diploid parthenogenesis may continue for many generations (as indicated by the long, broken-lined arrows). But the daughters of the amictic female may be "mictic" (M). Their eggs are haploid, and develop partheno- genetically (m) into males, or, if fertilized, produce non-sexual amictic females, the "stem mothers," with which the cycle begins anew. with the diploid number of chromosomes. From such a female, commonly spoken of as the stem mother, begins again the cycle of diverse generations just described. The purpose of the present investigation is to analyse this cycle in the species Lecane inermis; to give an account of the different. 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 Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass. : Marine Biological Laboratory
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
