. The elementary nervous system . Fio. 32.—Diagram of the jellyfish Aurelia from which the central mass and seven of the eight marginal bodies have been removed. The outline of the bell has been further complicated by a circular incision that has nearly divided the bell into two rings. The arrows show the course of the contraction wave as it emerges from the one remaining marginal body and passes over the bell. (After Romanes, 1893.) reducing it further by a circular cut parallel to its outer edge and midway between this edge and the center. The circular cut is so extended as to form a complet
. The elementary nervous system . Fio. 32.—Diagram of the jellyfish Aurelia from which the central mass and seven of the eight marginal bodies have been removed. The outline of the bell has been further complicated by a circular incision that has nearly divided the bell into two rings. The arrows show the course of the contraction wave as it emerges from the one remaining marginal body and passes over the bell. (After Romanes, 1893.) reducing it further by a circular cut parallel to its outer edge and midway between this edge and the center. The circular cut is so extended as to form a complete circle except for a fraction of an inch over which the outer ring is in organic connection with the inner one. When a wave of contraction is started from the one remaining mar- ginal body on the outer ring, it will, on arriving at the bridge, pass across to the inner one irrespective of the region in the bell at which the bridge may be located, thus
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Keywords: ., bookpublisherphiladelphialondonjblipp, booksubjectnervoussystem
