. On the anomalies of accommodation and refraction of the eye, witha preliminary essay on physiological dioptrics. of a thin fasciculus, a b, derived from the twonerve-sheaths, and this is covered anteriorly by the completely atro-phic pigmentless chorioidea, d. It appears, that the nerve, whichhere exhibits superiorly a perhaps accidental thickening, after itsfibres have lost the medullary sheath, is still thinner than inordinary cases, and thus goes inwards, through a smaller opening in thechorioidea, sometimes in an oblique direction, in order immediatelyas retina, n n, to spread itself ove
. On the anomalies of accommodation and refraction of the eye, witha preliminary essay on physiological dioptrics. of a thin fasciculus, a b, derived from the twonerve-sheaths, and this is covered anteriorly by the completely atro-phic pigmentless chorioidea, d. It appears, that the nerve, whichhere exhibits superiorly a perhaps accidental thickening, after itsfibres have lost the medullary sheath, is still thinner than inordinary cases, and thus goes inwards, through a smaller opening in thechorioidea, sometimes in an oblique direction, in order immediatelyas retina, n n, to spread itself over the anterior surface of the atrophicchorioidea. In the instructive drawings given by von Jaeger,* oneof which I have here copied (Fig. 147), the sheath of connectivetissue has for the most part not only extended upwards, but an ex-tremity of it also stretches between the layers of the sclerotic. VonJaeger further remarks, that the internal extremity of the nerve, withearly bending and spreading of its fibres, appears as it were drawnwithin the eye: in Fig. 147 (after Jaeger) the lamina cribrosa and Fie, the place where the nerve-fibres lose their medullary fibres, reallyappear to have approached nearer to the retina. The retina has in general a normal appearance. It is hard to saywhether it is more or less attenuated in one place or another; butthus much is certain, that the atrophy in this membrane cannot be * Ueber die Einstellungen, etc. Wien, 1861, Tab. i. and ii. 378 MYOPIA. compared with that in the sclerotic and chorioidea. The extendedcourse of the vessels, ahead} ophthalmoscopically seen, can be easilyproved : how far the proper tissue is altered, it is difficult to ,* who often examined the retina in staphyloma sclerotica?,in consequence of chorioiditis postica, found, with the exception ofsome empty places on the posterior layer (the layer of rods andbulbs), no changes in it. H. Muellert thinks that in one case hefound the tissue looser; but he hims
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