. The cell; outlines of general anatomy and physiology. r at theangle of the loop, which is directed towards the spindle, and com-mence to retreat towards the poles, whilst for a time the ends ofthe arms of the loop remain undivided. Finally these also splitup. From out of the 24 original loops two groups, each contain-ing 24 daughter-loops, have developed ; these move towards thecentrosomes, until they come quite close to them, when theystop, for they never actually reach the poles themselves. Be-tween these two groups fine connecting fibrils stretch ; theseare probably derived from the spind
. The cell; outlines of general anatomy and physiology. r at theangle of the loop, which is directed towards the spindle, and com-mence to retreat towards the poles, whilst for a time the ends ofthe arms of the loop remain undivided. Finally these also splitup. From out of the 24 original loops two groups, each contain-ing 24 daughter-loops, have developed ; these move towards thecentrosomes, until they come quite close to them, when theystop, for they never actually reach the poles themselves. Be-tween these two groups fine connecting fibrils stretch ; theseare probably derived from the spindle fibrils. Each loop, or daughter-segment, has its angle directed towardsthe pole, whilst its free ends are turned either obliquely, or per-pendicularly, to the equatorial plane. As might be expected, tostart with, they are much thinner than the mother-segments;however, they soon begin to shorten and to become proportion-ately thicker. When the daughter-star is first formed, thesegments lie somewhat far apart, but they soon begin to draw 188 THE CELL. more closely together, so that it becomes very difficult to countthem and to trace their further development; in fact, it can onlybe accomplished in exceptional cases. Fourth Stage of Division. During this stage each group of danghter-segments becomesgradually re-transformed into a vesicular resting nucleus (Fig. 81). The threads draw still more closely to-gether, become more bent and thicker;their surfaces grow rough and jagged, andsmall processes become developed exter-nally upon them, whilst a delicate nuclearmembrane develops around the wholegroup. The radiated appearance aroundthe centrosomes gradually grows less andless distinct, until it soon quite , also, the centrosomes and thespindle fibrils can no longer be distin-guished. It has not yet been decided whatthey develop into. In fact, their origin andtheir disappearance are equally shroudedin mystery. Near to the place where thecentrosome was situated a
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