288 PHYSIOLOGY. 



of an egg when it is first dropped into hot water, it is 

 exceedingly delicate and easily torn. The retina is the 

 only part of the eye that is sensitive to light, and on it the 

 images must be formed to produce distinct vision. 



The Cornea. The clear front part of the eye is the 

 cornea. It is a continuation of the sclerotic coat and is 



Ciliary Muscle 



Optic Nerve Choroid 



Fig 86. Horizontal Section of Right Eye. 



more bulging than the rest of the front of the eye, as can 

 be seen by taking a side view of the eye, or by noticing 

 some one who closes the eyelids and rolls the eyes about. 



The Iris. This is the part that gives the color to the 

 eye, or if the pigment that gives the color is lacking, the 

 blood gives the pink color seen in albinos. The iris is a 

 forward continuation of the choroid coat. 



