. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 172 KATSUMA DAN AND JEAN CLARK DAN the animal side of the blastomeres would greatly increase the efficacious force avail- able for the tearing open of the vegetal furrow. The most direct and decisive way to test this possibility is to interfere with the spinning activity and see whether or not the eggs can divide. A method of me- chanical intervention was adopted. It consisted in moving a micro-dissection needle back and forth along the furrow as the latter was being formed. It was thought that this method would prevent the
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 172 KATSUMA DAN AND JEAN CLARK DAN the animal side of the blastomeres would greatly increase the efficacious force avail- able for the tearing open of the vegetal furrow. The most direct and decisive way to test this possibility is to interfere with the spinning activity and see whether or not the eggs can divide. A method of me- chanical intervention was adopted. It consisted in moving a micro-dissection needle back and forth along the furrow as the latter was being formed. It was thought that this method would prevent the amalgamation of the protoplasmic processes. Special care was taken not to injure the sides of the furrow by the needle during the operation. The result was clear-cut. The eggs divided completely. But on completing cleavage, the blastomeres fell apart. Later it was found that a simpler way to achieve this aim is to make the eggs divide under compression in a hanging drop with an extremely small quantity of sea water. The tracings of photographs shown in Figure 6 illustrate an egg so treated. The reason for the failure of the spinning under compression is probably that, as the egg is flattened so much, the. 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
