Textbook of normal histology: including an account of the development of the tissues and of the organs . a single layer of regular poly-hedral plates, whose oval nuclei project slightly beyond the bodiesof the cells. Blood-vessels are absent in the cornea, except within a narrowzone, about i mm. in width, at the limbus or margin; in the fcetus,however, the vessels extend well towards the centre and form theprecorneal capillary net-work. The lymphatics of the cornea are represented by the system ofintercommunicating spaces and canaliculi; these clefts openinto lymphatic radicles at the peripher
Textbook of normal histology: including an account of the development of the tissues and of the organs . a single layer of regular poly-hedral plates, whose oval nuclei project slightly beyond the bodiesof the cells. Blood-vessels are absent in the cornea, except within a narrowzone, about i mm. in width, at the limbus or margin; in the fcetus,however, the vessels extend well towards the centre and form theprecorneal capillary net-work. The lymphatics of the cornea are represented by the system ofintercommunicating spaces and canaliculi; these clefts openinto lymphatic radicles at the periphery, which, in turn, communi-cate with the larger anterior lymphatic vessels. Perineurial lymph-channels enclose the larger nerve-trunks, which they accompanyfor a variable distance into the corneal tissue; these lymphaticchannels communicate directly with the corneal spaces at frequentintervals. The nerves of the cornea are very numerous, and are distributedlargely within the anterior layers. They enter at the corneal limbusas some sixty radially-disposed twigs, each of which includes from Fig. Subbasilar plexus of corneal nerves from rabbit; gold preparation. three to twelve fibres; the latter almost at once, within .5 mm. ofthe limbus, become non-medullated. Within the substantia propria the nerve-fibres form a coarseground-plexus at a level corresponding to about the middle thirdof the corneal tissue ; from this net-work twigs are sparingly givenoff to supply the deepest layers, while others pass towards the THE EYE AND ITS APPENDAGES. 341 anterior lamellae, in which they form net-works. Immediatelybeneath the anterior elastic membrane the smaller fibres form thedense subbasilar plexus, while under the epithelium the finestfibrillae constitute the subepithelial plexus, from which delicatenaked axis-cylinders ascend and enter the epithelium, to end betweenthe cells as the intra-epithelial plexus. THE SCLERA. The sclera is composed of the same elements as is the substanti
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Keywords: ., bookauthorpiersolgeorgeageorgea, bookcentury1800, bookdecade1890
