A treatise on zoology . Fia. VI. A Hinipli, nn-htanchf^d arm, thatof lliihfHTiuiin. II,riidiul ; lir, brachiai ; (•./(, covti ? THE CRINOIDEA lOI containing the geniliil cord or rachis {(j.()\ and a coeliac canal{ex). On cither side uf tlic water-vessel, hencath the tentacles, is asenso-motor nerve (/t2), giving off branches to the mnscles of the. Fio. of solid section of a Crinoid ami. For explanation of letters see adjoining text. water-canals and to sensory papillae (5) on the tentacles. Belowall these, in a special groove on the very floor of the main brachialgroove, lies anoth
A treatise on zoology . Fia. VI. A Hinipli, nn-htanchf^d arm, thatof lliihfHTiuiin. II,riidiul ; lir, brachiai ; (•./(, covti ? THE CRINOIDEA lOI containing the geniliil cord or rachis {(j.()\ and a coeliac canal{ex). On cither side uf tlic water-vessel, hencath the tentacles, is asenso-motor nerve (/t2), giving off branches to the mnscles of the. Fio. of solid section of a Crinoid ami. For explanation of letters see adjoining text. water-canals and to sensory papillae (5) on the tentacles. Belowall these, in a special groove on the very floor of the main brachialgroove, lies another nerve, the axial cord («.<;), proceeding fromthe aboral or dorsal motor nerve-system ; the groove in which thislies is often (as in Fig, VII.) separ-ated from the brachial grooveduring individual developmentby an outgrowth of stereom, andis then known as the dorsal or axial canal (Fig. VIII.). Theaxial cord sends off branches (7i3)to all the muscles of the arms,and to supposed sensory endings in the ectoderm (e^), and is con-nected with the subtentacular nerves. All these soft structuresin the ventral groove are protected by covering-plates (c;?), also
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishe, booksubjectzoology
