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vitreous (hyaloid membrane) is firmly attached to the front of 

 the choroid and that it holds the lens in a capsule behind the 

 pupil. Strip the hyaloid membrane and the lens hi its capsule 

 from the choroid, and observe how firmly attached it is to a 

 series of ridge-like thickenings of the choroid just behind the 

 junction of the cornea and sclerotic the ciliary processes. 

 Examine these processes. Note that the iris is continued 

 forward from them to the edge of the pupil. 



Shell the crystalline lens out of its capsule. Study its shape 

 and note its elastic character. 



Observe the aqueous humour in front of the lens and behind 

 the cornea, filling the anterior chamber. 



Now make a section through the cornea and sclerotic at 

 right angles to the last cut. Study and draw the cornea- 

 sclerotic junction. 



In the posterior segment of the eye note the entrance of 

 the optic nerve, and observe the thin membrane-like retina 

 spread over the choroid. Note the iridescence in front of the 

 choroid in the eye of the ox. Observe the blood vessels 

 entering in the optic nerve and spreading over the front of 

 the retina. (In the eye of the ox there is no special develop- 

 ment of a macula lutea in the posterior optic axis.) Make 

 drawings of the various structures seen. 



Revise the histology of the different structures. 



II. Examination of the Eye in Life. 

 Ophthalmoscope. 



Make a model eye by unscrewing the lower lens of a micro- 

 scope eyepiece and placing inside it a piece of paper with 

 some mark upon it. Look through the upper lens, and 

 observe that the chamber is dark and the paper is not dis- 

 tinctly seen. 



Direct Method. In the optical room fix the model eye 

 in the holder, and bring the electric light beside it so that it 

 does not shine on the front of the model. Using the mirror 

 with a hole in the centre, reflect light into the model eye, and 

 look into it through the hole. Begin at a distance of two feet 

 from the eye, and approach it keeping the light reflected 



