In a previous communication (Raven, Escher, Herrebout, & Leussink, 1958) the maturation of the egg was described in Agriolimax reticulatus, Limax flavus, and Limnaea stagnalis, with special regard to the formation of the second maturation spindle. In the three species the second maturation spindle arises by direct transformation from the deep centrosphere of the first maturation amphiaster. In A. reticulatus and Limax flavus this centrosphere contains a pair of centrioles which move apart to opposite poles of the developing spindle. This is symmetrical and develops an aster at both ends, arising in the cytoplasm outside the original centrosphere.

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