Class-book of physiology : for the use of schools and families : comprising the structure and functions of the organs of man, illustrated by comparative reference to those of inferior animals . THE SENSES. 181 commence in a small opening in the edge of each lid, nearthe corner of the eye, and unite to form the lachrymal sacthat lies upon the side of the upper parts of the nose,From the lachrymal sac a canal passes down to the interiorof the nose, where the tears pass off in vapor with the breath, 376: The Avails of the eye are composed of three coats:the sclerotic, the cornea, and the choroid
Class-book of physiology : for the use of schools and families : comprising the structure and functions of the organs of man, illustrated by comparative reference to those of inferior animals . THE SENSES. 181 commence in a small opening in the edge of each lid, nearthe corner of the eye, and unite to form the lachrymal sacthat lies upon the side of the upper parts of the nose,From the lachrymal sac a canal passes down to the interiorof the nose, where the tears pass off in vapor with the breath, 376: The Avails of the eye are composed of three coats:the sclerotic, the cornea, and the choroid coat Its interior isoccupied by three humors: the aqueous, the crystalline,and the vitreous. 377. The sclerotic, {fig. 55,) so named from its firmnessand density, constitutes about four-fifths of the globe ofthe eye. It is a tough fibrous structure, admirably adaptedto protect and support this delicate ;—Interior of the Eye. Fig. 56.—Section of the Eye. l, cornea ; s, sclerotic; s portion of the sclerotic turned back to show the subjacent pans;c/S, choroid; r, retina; n, optic nerve; ca, anterior chamber; t,iris; p,pupil: cr, crys-talline lens; ep, ciliary processes ; v, vitreous humor; I, b, conjunctiva. 378. The cornea (c, fig. 55) is a dense transparent struct-ure, convex in front and concave posteriorly. It resem-bles a watch-glass in form, and is received into a circulargroovein the margin of the sclerotic, in the same mannerthat a watch-glass is inserted into the case. It occupiesabout one-fifth of the front part of the eye, and projectsforward beyond the sclerotic. In some individuals and Where is the lachrymal sac situated, and how do the tears escape from it 1Of what are the walls of the eye composed ? How is its interior occupied?Describe the sclerotic. Describe the cornea. How is it received into thesclerotic ? What portion of the eye does it occupy ? What is sa
Size: 2321px × 1076px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1860, booksubjectphysiologicalprocess
