Transactions . -are attached posteriorly to the choroid. The fibres of Miilleiform the angular ring beneath those of Bowman. The physiologic action which follows would almost seemobvious. A contraction of the long fibres relaxes the with this, the circular fibres surrounding the mar-gin of the iris contract, impeding the free venous flow and caus-ing the ciliary processes to become turgid, with blood; they inttxrn pressing, by their bulk, on the anterior part of the sus-pensory ligament of necessity flatten the edges and protrude 187 the center of the lens in exactly the
Transactions . -are attached posteriorly to the choroid. The fibres of Miilleiform the angular ring beneath those of Bowman. The physiologic action which follows would almost seemobvious. A contraction of the long fibres relaxes the with this, the circular fibres surrounding the mar-gin of the iris contract, impeding the free venous flow and caus-ing the ciliary processes to become turgid, with blood; they inttxrn pressing, by their bulk, on the anterior part of the sus-pensory ligament of necessity flatten the edges and protrude 187 the center of the lens in exactly the form that catoptric testshave shown to be present. Accommodation having been completed, the muscles relaxallowing the vessels which had been full, to empty, in all prob-ability in doing so allowing the overflow to pass into Schlemmscanal. It will be evident from this that as the artery leads by way ofa very large capillary into the anastomosing mass of veins. Plate 2 \itreous Lens Portion of Greatest DensityIn the presence of the crystalline lens the traction on the supra-choroidea the ciliary bodies which fills with blood, as erectiletissues. The same eflfort forces forward the vitreous lens, whichpresses against the posterior part of the crystalline lens, its denserportion pushing forward the more plastic part in a lenticonus of thecurve necessary to meet the focal requirements. Its relaxation allowsthe blood from the ciliary bodies to flow into Schlemms canal, thevitreous lens slips back and the crystalline resumes its normal curvefor the eye at rest. the passage of blood into the capillary processes is practicallyunimpeded. That an increase in bulk in the ciliary region occursin accommodation, has been noted by Tscherning who does notascribe it, however, to the cause which I have given. He savs,There is formed during accommodation at the anterior surfaceof the iris a circular depression—the peripheral border of whichcorrespo
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectophthalmology, bookye
