9 o 



The Eye 



muscce volitantes. In the foetus a slender canal through the vitreous 

 transmits a branch of the arteria centralis retinae to the lens, iris, 

 and pupillary membrane. 



The canal of Schlemm is a narrow passage running all around 

 the eye-ball in the substance of the sclerotic, close to the attachments 

 of the cornea and iris. It is lined with endothelium, and, like the 

 anterior chamber, with which it is continuous, is part of the lymphatic 



c, cornea ; cs, conjunctiva ; Ch, choroid ; R, 

 retina ; v, vitreous , le, ligamentum pec- 

 tinatum ; s, sclerotic ; A, aqueous ; a/>, 

 posterior chamber of aqueous ; s v, canal 

 of Schlemm ; ir, iris ; io, cut fibres of 

 sphincter of pupil ; /, lens ; c, capsule ; 

 >, ciliary muscle ; dp, ciliary pro- 

 cesses ; 0, ora serrata ; h, hyaloid mem- 

 brane. (From QUAIN, by ALLEN 

 THOMSON.) 



system of the eye-ball. Its office is to drain away the nutrient fluid 

 which the ciliary processes supply for the vitreous, and which enters 

 the posterior chamber of the aqueous by permeating the suspensory 

 ligament of the lens ; and, in addition, to carry off the tide of the 

 aqueous, which, coming also from the ciliary processes, leaks into the 

 anterior chamber between the lens and the free border of the iris that 

 is, through the pupil. 



These aqueous tides flow into the canal of Schlemm through the 



