. Quain's elements of anatomy . -brane, and intranuclear network (fig. 10, ([) In addition to tlie nucleoplasmic fibres, the changes of which have been describedabove, other fibres may often be seen in the clear substance which occupies theends of the mother nucleus in the equatorial phase, converging- from the equatorto the poles; and, when the daughter-nuclei have become separated, bridging acrossthe inteival between them (see fig. 11). These fibres do not, like the others, becomestained with ha3matoxylin, and are hence termed achromatic by Flemming : theyare much better marked in some cells
. Quain's elements of anatomy . -brane, and intranuclear network (fig. 10, ([) In addition to tlie nucleoplasmic fibres, the changes of which have been describedabove, other fibres may often be seen in the clear substance which occupies theends of the mother nucleus in the equatorial phase, converging- from the equatorto the poles; and, when the daughter-nuclei have become separated, bridging acrossthe inteival between them (see fig. 11). These fibres do not, like the others, becomestained with ha3matoxylin, and are hence termed achromatic by Flemming : theyare much better marked in some cells than in others, and they probably exercisean important influence as guides, along which the movements of the otherfibres take place. In the division of the ovum, and in the multiplication of thenuclei of vegetable cells the achromatic fibres are exceedingly prominent andform a spindle shaped system of a characteristic aspect and looking at firstsight very different from those nuclei the division of which has just been Fig. Fig. 11.—Stages in the division op the ovum ok egg-cell op a worm. (Strasburger.) a, resting state; 6, nucleus transformed into a spindle-shaped system of fibres, whichare provided with thickenings at the equator of the spindle ; c, separation of equatorialthickenings into two parts which gradually travel towards the poles of the spindle andthere become transformed into new (daughter) nuclei, whilst the protoplasm at thesame time also separates into two parts {d, c, f) ; g, repetition of the division process,formation of spindles in daughter cells ; h, result of the division of these. (The nuclearfilaments shown in fig, 10 are here probably only represented by the thickenings at theequator of the spindle-shaped system, which is mainly formed by fine straight filaments,which stain far less with hsematoxyliu than the otheis, and on account probably of theirless distinctness and want of colouration aie not seen in the nuclei represented in tig. 10.) desc
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