. Biology of the vertebrates : a comparative study of man and his animal allies. Vertebrates; Vertebrates -- Anatomy; Anatomy, Comparative. Canal of Schlemm A g^^CircularFibers ) Ciliary ^^v^^Radial Fibers j Muscle Ik .Scler \ Ciliary Processes Suspensory Ligament. Fig. 715. Diagram illustrating the process of accommodation in the human eye. For near vision the ciliary muscles contract, drawing the region b nearer to the region a. The tension upon the ciliary ligament being diminished thereby, the lens assumes a more spherical shape, chiefly in the direction of the cornea with a consequent dis
. Biology of the vertebrates : a comparative study of man and his animal allies. Vertebrates; Vertebrates -- Anatomy; Anatomy, Comparative. Canal of Schlemm A g^^CircularFibers ) Ciliary ^^v^^Radial Fibers j Muscle Ik .Scler \ Ciliary Processes Suspensory Ligament. Fig. 715. Diagram illustrating the process of accommodation in the human eye. For near vision the ciliary muscles contract, drawing the region b nearer to the region a. The tension upon the ciliary ligament being diminished thereby, the lens assumes a more spherical shape, chiefly in the direction of the cornea with a consequent displacement anteriorly of the iris. These changes are indicated by broken lines; in the case of the iris, however, only the anterior surface is shown in the dis- placed position. (After Toldt.) small branches (Fig. 715). Although there are no openings from the spaces of Fontana into this canal, it is believed that fluid from the anterior cham- ber entering the spaces of Fontana may pass into the canal and thence into the blood stream. Possibly excess fluid is removed from the eyeball along this pathway. (c) Accessory Parts.—In addition to the eyeball itself there are certain acces- sory structures, namely, extrinsic muscles, glands, and shutter-like eyelids and eye- lashes, that are parts of the complex vertebrate eye region. The extrinsic mus- cles, that enable the eyeball to face in various directions without moving the entire head, have already been consid- ered (Fig. 584). They are inserted on the outside of the eyeball far enough for- ward so that, when contracted, they do not pull directly against their point of attachment, but against the curving surface of the eyeball, thus minimizing the liability of tearing loose (Fig. 716). Eyelids are transverse protective folds of the skin that close like shutters. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrat
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Keywords: ., bookcentury1900, booksubjectanatomycomparative, booksubjectverte
