This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1891 Excerpt: ...arrangement around each center. The space between the optic disks is now completely bridged over by a sheet of closely x crowded cells (T. Cd.), and the backward extension of this, and the approximation of the lateral cords has quite closed over the central or sterual region of this part of the embryo (St. A.). Cell ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1891 Excerpt: ...arrangement around each center. The space between the optic disks is now completely bridged over by a sheet of closely x crowded cells (T. Cd.), and the backward extension of this, and the approximation of the lateral cords has quite closed over the central or sterual region of this part of the embryo (St. A.). Cell outlines are very distinct at the surface in preparations, and they are sometimes well denned in cells which have passed from the surface to parts below it, in both the region of the optic disk and that of the ventral plate (Fig. 80, Ec.), but elements closely associated with yolk are usually amoeboid. The nucleus of the epiblastic or epithelial cell on the confines of the embryo, or on the extraembryonic surface of the egg, has the shape of a flattened, round, or oval disk. Epiblastic nuclei in the appendages and other parts of the embryo, where there is rapid cell division, are angular in consequence of crowding, and deep-lying nuclei are generally spherical. The arrangement of the embryonic cells of the superficial epiblast in beantiful curves and rings around definite centers--orthogouic systems of curves--is not nearly so pronounced as in the embryo crayfish (Astacus fluciatilia), according to the delineations of Reicheubach and Winter. Reicheubach states that in the crayfish the superficial embryonic cells multiply about a given center, like that of the "head fold" (optic disk), or "thoracic-abdominal rndiment," according to definite laws. This was discovered by Sachs in the growing tips of plants. According to Sachs, Reichenbach, and others, the cell nuclei always divide in one of two opposite planes; that is, they either separate along a radins drawn from a given center, thus giving rise to radial strings of cells, or...
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Seller's Description:
PLEASE NOTE, WE DO NOT SHIP TO DENMARK. New Book. Shipped from UK in 4 to 14 days. Established seller since 2000. Please note we cannot offer an expedited shipping service from the UK.
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Seller's Description:
PLEASE NOTE, WE DO NOT SHIP TO DENMARK. New Book. Shipped from UK in 4 to 14 days. Established seller since 2000. Please note we cannot offer an expedited shipping service from the UK.
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Seller's Description:
Washington 1891. Article at pp. 321-576, 57 colored plates of crayfish in one complete volume of the Memoirs of the National Academy of Sciences, Volume V, 1891. Includes A few additional articles on other topics in volume as well. Hardcover. 4to., maroon cloth. Good, head of spine frayed, light wear. No ownership marks. Not a modern reprint.
