590 



THE EYE. 



name of lamina crihrosa is sometimes given. Around this cribrous 

 opening are smaller apertures for vessels and nerves 



Fig. 399. 



Fig. 399. — View of the Loweu Half of the ?aGHT Adult Human Eye, divided 



HORIZONTALLY THROUGH THE MIDDLE. MAGNIFIED FOUR TIMES. (A. ThOBISON.) 



The specimen from which this outline is taken was obtained by dividing the eye of a 

 man of about forty years of age in the frozen state. It w-as carefully comiiared with 

 other specimens obtained in a similar manner ; and in the drawing averages have been 

 given in any particulars in which differences among them presented themselves. 



1, the cornea ; l',its conjunctival layer; 2, the sclerotic ; 2', sheath of the optic rerve 

 passing into the sclerotic ; 3, 3', the choroid ; 4, ciliary muscle, its radiating portion ; 4', cut 

 fibres of the circular portion ; 5, ciliary fold or process ; 6, placed in tlie posterior division of 

 the aqueous chamber, in front of the suspensory ligament of the lens ; 7, the iris (outer or 

 malar side) ; 7', the smaller, innor, or nasal side ; 8, placed on the divided optic nerve, 

 points to the arteria centralis retinas ; 8', colliculus or eminence at the passage of the 

 optic nerve into the retina ; 8", fovea centralis retina ; r, the nervous layer of the retina ; 

 5-', the bacillar layer ; 9, ora serrata at the commencement of the ciliary part of the 

 retina; 10, canal of Petit ; 11, anterior division of the aqueous chamber in front of the 



