TECHNIQUE OF EYE DISSECTIONS 



little better than will the longitudinal section. 

 In cutting the longitudinal section, one is 

 sometimes so fortunate as to cut through the 

 central blood vessels of the retina, These ves- 

 sels will show up then as a rather thin dark 

 streak about 5 or 6 mm. long. 



THE ANTERIOR HALF 



The anterior half will show the lens in situ, 

 the ciliary processes, the posterior aspects of 

 the iris and the lens, the corona ciliaris, the 

 orbicularis ciliaris, and the ora serrata, (Fig. 

 16.) If the eye has been cut in two too far 

 forward of its equator, the ora, serrata will 

 not be present. The ciliary processes and pos- 

 terior aspect of the lens may be seen to better 

 advantage when the anterior half of the vit- 

 reous is removed. This is done with the dull- 

 pointed tweezers, by c'atching hold of the vit- 

 treous at any part of its free or cut margin, and 

 stripping it off both the ciliary processes and 

 the lens, using a prying, pulling movement to 

 do so. (Fig. 17.) The two layers of the pig- 

 ment cells, pars ciliaris retinae, which cover 



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