Observations on the arrangement of the fibres in the optic nerve of the loligo and other animals.

  • Power, John H. (John Hatch), 1806-1863.
Date:
1842
Catalogue details

Licence: Public Domain Mark

Credit: Observations on the arrangement of the fibres in the optic nerve of the loligo and other animals. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    whilst performing this traction, the decussation was most strik- ingly apparent. The inner fibres had the appearance of being arranged in plates laid one over the other, and passing between each other, to form the nerves of opposite sides. In the human subject, the parts are exceedingly complex ; on laying open the optic tract, close to its origin, and spreading out its fibres, they were seen interlacingwith each other in such away, as to elude all attempts at following their course, the superficial surface of the tract does, however, present another example of the peculiar appearance I have noticed already : the fibres are here also twisted on each other, so as to give to the tract, when perfectly stripped of all its mem- branes, and as it is about to form the commissure, a stranded or rope-like appearance. On per- forming the same tractions with these parts, as with those of the sheep and owl, the arrangement of the fibres, as represented in Fig. 5, was quite obvious j the su- perficial fibres are here seen torn through, and taking the same course with regard to the tract and commissure, which they ap- peared to do, when viewed with a lens before disturbing the parts themselves. More deeply seated we observe, in the same figure, the arrangement of the internal fibres; they may be seen in the preparation distinctly, as they are represented in the engraving, by the unassisted eye, arranged in plates, the fibres of these plates interlacing with those of the opposite side. It results, therefore, from the disposition of the parts now described, that the nervous fibres do not run in such a direction
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