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HATsD-BOOK OF PHYSIOLOGY. 



and scaly, and the deeper ones more or less columnar. Immediately 

 beneath this is the anterior elastic lamina (Bowman). 



The cornea tissue proper as well as its epithelium is, in the adult, 

 completely d3stitute of blood-vessels; it consists of an intercellular ground- 

 substance of rather obscurely fibrillated flattened bundles of connective 

 tissue, arranged parallel to the free surface, and forming the boundaries 



FIG. 367. Vertical section of rabbit's cornea, a, Anterior epithelium, showing the different shapes 

 of the cells at various depths from the free surface; 6, portion of the substance of cornea. (Klein.) 



of branched anastomosing spaces in which the cornea-corpuscles lie. These 

 branched cornea-corpuscles have been seen to creep by amoeboid move- 

 ment from one branched space into another. At its posterior surface the 

 cornea is limited by the posterior elastic lamina, or membrane of Descemet, 

 the inner layer of which consists of a single stratum of epithelial cells 

 (Fig. 366, d). 



Nerves of Cornea. The nerves of the cornea are both large and 

 numerous: they are derived from the ciliary nerves. They traverse the 



FIG. 368. Horizontal preparation of cornea of frog; showing the network of branched cornea 

 corpuscles. The ground substance is completely colorless. X 400. (Klein.) 



substance of the cornea, in which some of them terminate, in the direc- 

 tion of its anterior surface, near which the axis cylinders break up into 

 bundles of very delicate beaded fibrillge (Fig. 366): these form a plexus 

 immediately beneath the epithelium, from which delicate fibrils pass up 



