Journal of morphology . of equal value, structurally and functionally, with thelatter. 32 A VERS. [Vol. VI. Man (Cut ii). In Man and other mammalia the utriculus^ forms a smallchamber, from which are given off seven processes. Five of these belong to the canals ; the othertwo are the canalis reuniens and theutricular blind sac. The utriculusU and sacculus, although nearly equalin size, are very small relative to thelong, enlarged cochlea, and they arerelatively of less importance than inthe Alligator. SACCULUS. The saccular regiofT of the Tor-pedo, viewed from the side, is asomewhat sickle-sha
Journal of morphology . of equal value, structurally and functionally, with thelatter. 32 A VERS. [Vol. VI. Man (Cut ii). In Man and other mammalia the utriculus^ forms a smallchamber, from which are given off seven processes. Five of these belong to the canals ; the othertwo are the canalis reuniens and theutricular blind sac. The utriculusU and sacculus, although nearly equalin size, are very small relative to thelong, enlarged cochlea, and they arerelatively of less importance than inthe Alligator. SACCULUS. The saccular regiofT of the Tor-pedo, viewed from the side, is asomewhat sickle-shaped body, withthe cutting edge of the sickle bladedirected forwards, downwards, out-wards. The sacculus proper is abroadly rounded sac with scarcely aconstriction where it opens into thecommon utriculo-saccular chamberabove. The long axis of the sacbends backwards and outwards fromthe axis of the common chamber ofthe ear, while its lagenar prolonga-tion carries the axis forwards by abend at the point of origin from the. Ctit II. —The left internal earof a human embryo, 22 mm. inlength, seen from without and be-low. Figure after W. His, figure is from a model con-structed from serial sections, andrepresents the ear much magni-fied, a, anterior canal; am, am-pulla; am, amae (the middlereference line is superfluous);c, cochlea; d, ductus endolym-phaticus; /;, external canal; j, sac-culus (in the restricted sense;really only the recessus sacCuli);u, utriculus. sacculus. The sacculus possessesone of the canal sense organs, and its lagenar prolongation con-tains a bud from this organ which in the higher forms growsout into and forms the major portion of the cochlear utriculo-saccular chamber of other vertebrates, as of theforms described above, is really the transformed canal of theprimitive auditory organ, some of the offspring remaining inthe parental canal with parent organs just as the macula abortiva 1 It should not be forgotten that the utriculus of these for
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Keywords: ., bookauthorwistarin, bookcentury1800, bookdecade1890, bookyear1892
