. Journal of anatomy . x the Hixd Braix. We have already pointed out that the auditory syncytium, the y-neuroblasts in the hind brain, the neuro-epithelium and the y-neuroblastsin the middle of the syncytial tract, become fibrillated simultaneously. Theresulting neuro-librillas thus form one continuous bond of union betweenthe neuro-epithelium and the hind brain. This conclusion is in direct Development of the Auditory Nerve in Vertebrates 129 antagonism to the usually accepted view of continuitj^ of the peripheralauditory tract. Thus Retzius (19), Lenhossek (15), Katz (13) and othershave show
. Journal of anatomy . x the Hixd Braix. We have already pointed out that the auditory syncytium, the y-neuroblasts in the hind brain, the neuro-epithelium and the y-neuroblastsin the middle of the syncytial tract, become fibrillated simultaneously. Theresulting neuro-librillas thus form one continuous bond of union betweenthe neuro-epithelium and the hind brain. This conclusion is in direct Development of the Auditory Nerve in Vertebrates 129 antagonism to the usually accepted view of continuitj^ of the peripheralauditory tract. Thus Retzius (19), Lenhossek (15), Katz (13) and othershave shown, by means of the Golgi method, that the peripheral and centralfibres of the auditory nerve end in arborisations round the neuro-epitheliumand the cells in the hind brain respectively. It is surprising to note howreadily the appearances presented by Golgi preparations of the centralnervous system have been accepted by histologists without question orcomment. Our results with this method on nerve endino-s have not been. Fig. 20.—Tlie auditory ganglion and nerve and the hind brain of a youngfrog. Note the -y-neuroblasts of the ganglion and liind lirain andthe j3-neuroblasts of the nerve. convincing enough to warrant our placing implicit confidence in its action on embryonic tissues is undoubtedly very disappointing. Theiron-alum-hasmatoxylin method is, to our way of thinking, much moresatisfactory and more immune from ambiguity in the interpretation of theappearances presented by the tissues. Certainly, in the embryos of verte-brates below the rank of man, this mode of staining demonstrates not acontiguity by synapse but a direct anatomical continuity of the peripheralauditory tract. Of course it is possible that the conditions which prevailduring embryonic life may become profoundly modified by the time fullmaturity has been attained; but our investigations on more mature tissuesby the iron-alum-hoematoxylin stain have so far convinced us that this is 130 Dr John Came
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