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Home  »  Anatomy of the Human Body  »  pages 1019

Henry Gray (1825–1861). Anatomy of the Human Body. 1918.

pages 1019

the suspensory ligament there is a sacculated canal, the spatia zonularis (canal of Petit), which encircles the equator of the lens; it can be easily inflated through a fine blowpipe inserted under the suspensory ligament.
  No bloodvessels penetrate the vitreous body, so that its nutrition must be carried on by vessels of the retina and ciliary processes, situated upon its exterior.


FIG. 883– The upper half of a sagittal section through the front of the eyeball. (See enlarged image)

The Crystalline Lens (lens crystallina).—The crystalline lens, enclosed in its capsule, is situated immediately behind the iris, in front of the vitreous body, and encircled by the ciliary processes, which slightly overlap its margin.
  The capsule of the lens (capsula lentis) is a transparent, structureless membrane which closely surrounds the lens, and is thicker in front than behind. It is brittle but highly elastic, and when ruptured the edges roll up with the outer surface innermost. It rests, behind, in the hyaloid fossa in the forepart of the vitreous body; in front, it is in contact with the free border of the iris, but recedes from it at the circumference, thus forming the posterior chamber of the eye; it is retained in its position chiefly by the suspensory ligament of the lens, already described.
  The lens is a transparent, biconvex body, the convexity of its anterior being less than that of its posterior surface. The central points of these surfaces are termed respectively the anterior and posterior poles; a line connecting the poles constitutes the axis of the lens, while the marginal circumference is termed the equator.