The brain as an organ of mind . the nerve cell, and similarly emerges therefrom, sothat the cell in this case is only a nucleated expansion ofthe fibre. The fibrils of the axis band may be seen pass-ing through the cell in a divergent and re-convergentfashion, having the finely granular basis substance of thecell between them. The sheath of the fibre, thoughusually not the medullary substance (fig. 10), also passesover the cell. A point which will be found more doubtful in other casesis most distinctly illustrated here : viz., that a struc-tural continuity exists between the substance of the c
The brain as an organ of mind . the nerve cell, and similarly emerges therefrom, sothat the cell in this case is only a nucleated expansion ofthe fibre. The fibrils of the axis band may be seen pass-ing through the cell in a divergent and re-convergentfashion, having the finely granular basis substance of thecell between them. The sheath of the fibre, thoughusually not the medullary substance (fig. 10), also passesover the cell. A point which will be found more doubtful in other casesis most distinctly illustrated here : viz., that a struc-tural continuity exists between the substance of the celland that of the nerve fibre. There is no distinct line ofdemarcation between the two. But, so far as we know atpresent, this particular relation of fibre and eel] existsprincipally in ganglia peculiar to the ingoing ner ves andsituated near the great centres to which these are is, it is true, some reason for believing that asimilar relationship may exist in some of the ganglia on Chap. IL] A NERVOUS SYSTEM. 41. Fig 10.—Three bipolar Ganglion Cells from the fifth nerve of the Pike (Striekerafter Bidder). Fig. 11.—Three bipolar Ganglion Cells from the auditory nerve of the Pike : enclosed within the medullary sheath ; b, entirely, and c, partially, exposed,to show that these ganglion cells are only expansions of the axis band. the visceral nerves, and tha-t something hke it also exists, 42 THE STRUCTURE OF
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