. Elements of histology. Histology. JRIS. 437 where there are no pigment granules This enchj- theliuiu is called the uvea, or iapetum nigrum. The interstitial cement substiince between the cells is not pig- mented, but transparent. The name "uvea" is some- times applied to the whole of the iris, ciliary processes, and choroid membrane. In blue eyes the posterior epithelium is the only pigmented part of the iris, and so it is also in new-born children, whose iris appears blue. In all cases where the iris appears blue, this is due to the dark back — the pigmented epithelium of the
. Elements of histology. Histology. JRIS. 437 where there are no pigment granules This enchj- theliuiu is called the uvea, or iapetum nigrum. The interstitial cement substiince between the cells is not pig- mented, but transparent. The name "uvea" is some- times applied to the whole of the iris, ciliary processes, and choroid membrane. In blue eyes the posterior epithelium is the only pigmented part of the iris, and so it is also in new-born children, whose iris appears blue. In all cases where the iris appears blue, this is due to the dark back — the pigmented epithelium of the posterior surface—being viewed throutjh a dull layer— the substance of the iris. 421. Near the pupillary border the posterior section of the substantia propria contains a broad layer of circular bundles of non-striped muscular tissue : this is the spliincter pupiUct. In connection with this are bundles of non-striped mus- cular fibres, passing in a radi- ating direction towards the ciliary margin of the iris : these are the bundles of the dila- tator pupiUc(;, forming a sort of thin membrane near the posterior surface of the iris (Henle and others). At the ciliary margin the bundles take a circular direction and form a plexus (Ivanoff).. Fi-; I - vessels I injected) uf the Iris and Choroid Membrane of the Eye of a Child. {Kolliker, after Arnold.) a, Capillaries of the choroid ; b, era serrata; c, iilood- vessels connected with, d, those of the ciliary pro- cesses, and with e, those of the iris; /, capillary network of the pupillary Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Klein, E. (Edward), 1844-1925; Edkins, John Sydney, b. 1865. Philadelphia : Lea Brothers
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisherphiladelphialeabro
