The development of the human body; a manual of human embryology . Fig. 242.—Reconstruction op the Otocyst of an Embryo of , Cochlea; de, endolymphatic duct; sc, semicircular canal. —(.His, Jr.) THE INTERNAL EAR. 463 seems to be formed by the ductus dividing proximallyinto two limbs, one of which is connected with the utri-cle and the other with the saccule. When first observed in the human embryo the auditoryganglion is closely associated with the geniculate ganglionof the seventh nerve (Fig. 241, B), the two, usuallyspoken of as the acustico-facialis ganglion, forming a mass. Fig. 2
The development of the human body; a manual of human embryology . Fig. 242.—Reconstruction op the Otocyst of an Embryo of , Cochlea; de, endolymphatic duct; sc, semicircular canal. —(.His, Jr.) THE INTERNAL EAR. 463 seems to be formed by the ductus dividing proximallyinto two limbs, one of which is connected with the utri-cle and the other with the saccule. When first observed in the human embryo the auditoryganglion is closely associated with the geniculate ganglionof the seventh nerve (Fig. 241, B), the two, usuallyspoken of as the acustico-facialis ganglion, forming a mass. Fig. 243.—Reconstruction of the Otocyst of an Embryo of 22 , Cochlea; de, endolymphatic duct; s, sacculus; ut, utriculus.—(His, Jr.) of cells lying in close contact with the anterior wall of theotocyst. The origin of the ganglionic mass has not yetbeen traced in the mammalia, but it has been observedthat in cow embryos the geniculate ganglion is connectedwith the ectoderm at the dorsal end of the first branchialcleft (Froriep), and it may perhaps be regarded as one of 464 THE DEVELOPMENT OF THE HUMAN BODY. the epibranchial ganglia (see p. 440), and in the lowervertebrates a union of the ganglion with a suprabranchialganglion has been observed (Kupfer), this union indicat-ing the origin of the auditory ganglion from one or moreof the ganglia of the lateral line system. At an early stage in the human embryo the auditoryganglion shows indications of a division into two portions,a more dorsal one, which represents the future ganglionvestibulare, and a ventral one, the ganglion co
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectembryol, bookyear1902
