. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. POLYP1FEUA. The growth of the horny polypary exactly keeps pace with the development of the soft substance, and even goes beyond it. Below the tentacula the body soon becomes con- stricted, marking the boundary between it and the stem; and soon the polype, becoming too large to be contained in its sheath, issues forth, and expanding its tentacula becomes perfectly unfolded. The oviferons pedicles, hereafter to be described, are developed sub- sequently. Fig. Tubuluria coronata, magnified. a, stalk; b, walls of the p
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. POLYP1FEUA. The growth of the horny polypary exactly keeps pace with the development of the soft substance, and even goes beyond it. Below the tentacula the body soon becomes con- stricted, marking the boundary between it and the stem; and soon the polype, becoming too large to be contained in its sheath, issues forth, and expanding its tentacula becomes perfectly unfolded. The oviferons pedicles, hereafter to be described, are developed sub- sequently. Fig. Tubuluria coronata, magnified. a, stalk; b, walls of the polypary; c, substance common to all the individuals, whereby they are brought into mutual organic communication; d, limit between the individual and the community; <7, the long tentacles ; h, the short tentacles ; k, col- lar formed by the tentacles ; o, ova; n, a bud ; p, a bud further developed; q, a bud still further ad- vanced, showing indications of the two rows of tentacles (g, /(). {After Van ;) Second mode of propagation, by free gemmee. —The free gemmae are produced upon dis- tinct pedicles, which in the genus Tubularia are developed within the lower circle of ten- tacula. They resemble numerous appendages disposed in a circle and forming a crown around the body of the polype. (Fig. 48, o.) These pedicles grow in the same manner as the buds and the tentacula described above, that is to say, a hollow tubercle first makes its appearance, which seems to be merely an extension of the external covering of the polype. Each tubercle slowly expands, and soon divides into one or more branches, which are all hollow, and the same fluid which circulates in the general substance of the polype may be observed to pass into their interior. At the free extremity of each of the pedicles thus formed a distinct cell is soon perceptible, situated im- mediately beneath the surface, which cell is the rudiment of a new in- dividual. (Fig. 49, !,«.) No nucleus has been rema
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