. The cell; outlines of general anatomy and physiology. Fig. 82. — Egg of Ascarismegalocephala undergoing theprocess of double are resting; the cen-trosomes as yet undivided.(After Boveri, PI. IV., Fig. 74.) 190 THE CELL what was formerly the pole of the division figure; it is enclosedin granular protoplasm, which contracts with the yolk substanceof the egg, and has been named by van Beneden the attractionsphere, and by Boveri the archoplasm. Before the nucleus has quite returned to the resting condition,and even sometimes before the first division is completed, it com-mences t
. The cell; outlines of general anatomy and physiology. Fig. 82. — Egg of Ascarismegalocephala undergoing theprocess of double are resting; the cen-trosomes as yet undivided.(After Boveri, PI. IV., Fig. 74.) 190 THE CELL what was formerly the pole of the division figure; it is enclosedin granular protoplasm, which contracts with the yolk substanceof the egg, and has been named by van Beneden the attractionsphere, and by Boveri the archoplasm. Before the nucleus has quite returned to the resting condition,and even sometimes before the first division is completed, it com-mences to make preparations to divide a second time ; these startwith changes in the centrosome (Fig. 84), which extends itself. Fig. &3. Fig. 81. Fig. 83.—Dividing egg of Atcaris megaloceplinJa. The nuclei are preparing to divide;the centrosomes are divided. (After Boveri, PI. IV., Figs. 75, 76.) Fig. 81.—Two daughter-nuclei with lobulated processes commencing to reconstructthemselves. The centrosomes are multiplying by self-division. (After van Beneden budNeyt, PL VI., Fig. 13.) longitudinally parallel to the first division plane, becomes biscuit-shaped, and divides itself by a constriction into two daughtercentrosomes, which for a time are enclosed by one common granu-lar sphere; these phenomena were discovered by van Beneden(VI. 4b) and Boveri (VI. 6, 1888). Next, the two centrosomesseparate somewhat from one another (Fig. 83), in consequence ofwhich their common radiation sphere becomes converted into twospheres. This division of the centrosomes gives the signal, as it were,for the occurrence of the following changes in the nucleus,although the latter is not yet completely at rest (Fig. 83). Thenuc
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