384 NEUROLOGY, OR ANATOMY OF NERVOUS SYSTEM 



are divided into a larger and a smaller set, the former being 

 about one-tenth inch in length. Their inner surface is covered 

 by the layer of hexagonal pigmented cells of the retina. 



The choroid is really a plexus of fine bloodvessels. Externally 

 it presents a membrane, the lamina suprachoroidea, between 



FIG. 67 



Canal of Schlemm. 



Posterior 

 chamber. 



CUiary 



body. 



Ciliary 

 processes. 



External 

 rectus 

 muscle. \ 



Cavity occupied 

 by vitreous humor. 



Canal of 

 Petit. 



Internal 

 rectus 

 muscle. 



Retina. 



Choroid 

 coat. 



Canal for 

 central artery. 



Sclerotic coat. 



Nerve ske^A ' ^~ Optic ne n e. 

 A horizontal section of the eyeball. (Allen.) 



which and the lamina fusca is a lymph-space which commu- 

 nicates with the capsule of Tenon through apertures in the 

 sclerotic. 



The ciliary muscle is a circular plane of unstriped muscle 

 placed between the choroid and sclerotic at its anterior part. 



