. Cytology, with special reference to the metazoan nucleus. Cells. m â y -â ; '% *â :'â :â xbl. Fig. 82. The chondriosomes in the fertihzation and cleavage of the guinea-pig's o\Tim. (After Lams, ^ .B., 1913.) A, entry of the spermatozoon ; B, 2-cell stage, the tail (including the chondriosome apparatus) of the spermatozoon lying unchanged in one blastomere. I., first polar body; II., second polar body ; t, tail of spermatozoon ; II., metaphase II. a complete hereditary outfit. It has, however, been rendered still more improbable â if not indeed definitely disproved â by Meves himsel
. Cytology, with special reference to the metazoan nucleus. Cells. m â y -â ; '% *â :'â :â xbl. Fig. 82. The chondriosomes in the fertihzation and cleavage of the guinea-pig's o\Tim. (After Lams, ^ .B., 1913.) A, entry of the spermatozoon ; B, 2-cell stage, the tail (including the chondriosome apparatus) of the spermatozoon lying unchanged in one blastomere. I., first polar body; II., second polar body ; t, tail of spermatozoon ; II., metaphase II. a complete hereditary outfit. It has, however, been rendered still more improbable â if not indeed definitely disproved â by Meves himself, who later (1914) traced the chondriosome mass of the male gamete in Parechinus up to the 32-ceU embryo. At this stage it is still compact and unchanged, and is therefore of course only to be found in one cell. AU the other 31 ceUs therefore contain no part of the male chondriosome apparatus, so that it is estabUshed that this is not essential to the develop- ment of the Echinoderm. Whilst thus the behaviour of the male chondriosome mass in fertihzation is alone enough to destroy all claim to the idioplasmic nature of chondriosomes, unless and until new knowledge of an unfore- seen nature is forthcoming, there are several other almost equally con- vincing items of evidence. It is not necessary to labour the point of the colossal excess of the chondriosomes in the egg over those brought in. 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 Agar, Wilfred Eade, 1882-. London, Macmillan
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectcells, bookyear1920
