404 



JAMES ROLLIN SLONAKER 



is shown in figure 4, Scl. This figure also shows that these 

 plates are decidedly bent similar to the italic letter /. This 

 bony ring, resting directly on the dense cartilage layer, gives to 

 the front of the eye a certain degree of firmness and yet one 

 which is capable of alteration. The ability to modify the shape 

 of this anterior portion could be accomplished in no^ better way. 

 The fact that this bony ring is made up of individual segments 

 capable of moving on each other indicates that this arrangement 



Fig. 32 Portion of an equatorial section through the ciliary region, showing 

 the CM, ciliary muscles; C^, ciliary processes; Scl, sclera; and Scl, scleral plates. 

 X 20. 



is for some other purpose than simply that of stiffening the 

 wall of the eye. The fact also that in sections of different eyes 

 these plates show different degrees of bending leads one to con- 

 clude that changes in shape have occurred. These facts, 

 coupled with the close relation of the muscles of accommodation 

 to the sclerotic bones, lead me to conclude that their primary 

 function has to do with accommodation. This will be discussed 

 more in detail later. 



Some differences are seen in the size of these plates. Table 2, 

 which gives the dimensions of these bones at four different loca- 



