On the function performed by the ciliary processes, and by the pecten, in the adjustment of the eye to distinct vision at different distances / by George Rainey.

  • Rainey, G. (George), 1801-1884.
Date:
1851
Catalogue details

Licence: Public Domain Mark

Credit: On the function performed by the ciliary processes, and by the pecten, in the adjustment of the eye to distinct vision at different distances / by George Rainey. 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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    ON THE FUNCTION PERFORMED BY THE CILIARY PROCESSES AND BY THE PECTEN, IN THE ADJUSTMENT OF THE EYE TO DISTINCT VISION AT DIFFERENT DISTANCES. The ciliary processes and the pecten being only secon- darily engaged in the act by which the eye adapts itself to distances, and being dependent upon the change produced in the position of the lens, and in the form of the vitreous humour, by the ciliary muscle, it will be necessary first to consider the anatomy of this muscle; and as the ciliary muscle has its highest state of development in birds, I shall describe it more particularly as it exists in that class of animals. The ciliary muscle in birds was discovered by Sir P.Crampton as early as 1818.* It is situated behind the more flattened part of the sclerotic coat, between it and the ciliary processes. It may be said to take its origin from some fibrous plexiform tissue, (described by Mr. Bowman,) continuous with the pos- terior elastic lamina of the cornea, close to some passages, appearing like large areolar spaces, called the canals of Fontana, and also from the adjoining part of the sclerotic coat, and passing from thence backwards, for the distance of one-eighth of an inch, to be inserted into the choroid coat at its junction with an elastic membrane connecting the choroid with the sclerotic. The ciliary muscle has, in front of it the sclerotic coat, over which its fibres can freely glide; below and behind it, the elastic tissue connecting the iris with the This description applies to the eye of the common fowl.