Volume 1

The microscopic anatomy of the human body, in health and disease. Illustrated with numerous drawings in colour / By Arthur Hill Hassall, M.B.

  • Hassall, Arthur Hill, 1817-1894.
Date:
1849
Catalogue details

Licence: Public Domain Mark

Credit: The microscopic anatomy of the human body, in health and disease. Illustrated with numerous drawings in colour / By Arthur Hill Hassall, M.B. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    are deposited. It has a regular arrangement, and is not free to change its place in the endolymph. Otolithes consist always of carbonate of lime. Of the Vestibular Nerves.—“ In consequence of the thick- ness of the wall of the membranous labyrinth where the nerves enter, and the presence there of the calcareous and fibrous matter, it is not easy to ascertain with certainty the precise manner in which the nerves terminate. In the utri- cule and saccule, they appear to spread out from one another as they enter, and then to pass, some to mingle with the calcareous powder, others to radiate for a small extent on the inner surface of the wall of the cavity, where they come into connection with a layer of dark and closely set nucleated cells, and presently loose their white substance. We have seen a fibrous film on the inner surface of these parts which we are disposed to consider as formed, like the inner surface of the retina, by the union of the axis-cylinders of the nerve tubes, but confirmatory observations are required. Those that traverse the calcareous clusters have appeared to us, in the most lucid views we have succeeded in obtaining, to terminate by free, pointed extremities, without losing their white substance. In the frog this has been evident enough. “ The nervous twigs belonging to the semicircular canals do not seem to advance beyond the ampullae, in which they have a remarkable distribution, entering them, as Steifen- sand has well shown, by a transverse or forked groove, on their concave side, and which reaches about a third round. Within this, the nerve projects so as to form a sort of trans- verse bulge within the ampulla. Their precise termination can be best seen in the osseous fishes, and has been de- scribed by Wagner to be loop-like. We believe we have seen this mode of termination, though certainly never so plainly as the figure given by this excellent author would indicate ; and we may add that we have found free extrem- ities to the nerve tubes, as well as loopings, in the ampulla; of the cod. The difficulty in these cases of ascertaining the exact truth arises from the curves formed by the nerve tubes