Observations on the canal of petit / by Thomas Spencer Cobbold.

  • Cobbold, T. Spencer (Thomas Spencer), 1828-1886.
Date:
MDCCCLII [1852]
Catalogue details

Licence: Public Domain Mark

Credit: Observations on the canal of petit / by Thomas Spencer Cobbold. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    The explanation I have given of the manner in which the hyaloid is folded, so as to form the cavity of the canal of Petit, is borne out by the examination of the eye in earlier stages of formation. At first the ring-shaped fringe, when relieved from its coverings, exhibits the form of a blunt circular ridge, or obtuse eleva- tion, a transverse section of which is represented in fig. 3. Its subsequent phases are exhibited in figs. 4, 5, and 6. In the adult eye, it is no longer a loose fold, merely confined within the space it occupies, but is adherent by its exterior surface to the hyaloid behind, and to the membranula of Zinn in front. This adhesion in the adult accounts for the structure not having hitherto been observed, and indicates in the embryo the existence of three ring-shaped spaces, 1, 2, 3, fig. 2, commimicating originally with one another, being the three corners of the cavity,—between the hyaloid, the membranula of Zinn, and the margin of the capsule of the lens,—which con- tains the festooned hollow fringe xmder consideration.^ ' This Paper forms a short abstract of the author's Inaugural Dissertation, which obtained one of the gold medals adjudged by the Medical Faculty of the University of Edinburgh. August 1, 1851. « MDRIIAV ANh OlbB, flHNTl2hS, KDINntmoH,