PLATE 12 



EXPLANATION OF FIGURES 



Microphotographs of sections through the pecten. 1, arteries; 2, veins of 

 pecten; A, artery at base of pecten just before and after entering eye; Op. n 

 optic nerve; C, cartilage of sclerotic much thickened at the nerve entrance; 

 P, folds of pecten; .S, sclera; V, vein at base of pecten. 



68 Section almost parallel to the pecten and perpendicular to the retina, 

 showing optic nerve entrance, Op N, and a portion of the crest of the pecten. 

 A portion of the basilar vein is seen at V. X 38. 



69 Section almost parallel to the pecten through the lateral portion of 

 pectinal folds some distance from where the optic nerve first pierces the 

 sclerotic. X 38. 



70 Section more distant from the first or jn-imary optic nerve entrance, show- 

 ing how the distal portion of the nerve lies under or within the sclerotic. X 38. 



71 Section at right angles to the folds of the pecten, showing the folded 

 arrangement and the location of the arteries, 1, and veins, 2. X 38. 



72 Section at right angles to the folds of pecten near its base showing the 

 basilar artery, A-A, and basilar vein, V-V, also the arteries, 1, and veins, 2, of 

 the folds of the pecten. X 38. 



73, 74, 75 Section at right angles to optic nerve almost parallel to folds of 

 pecten showing basilar artery, ^4, and vein, V, cut across. 



74 Shows where the artery enters from the outside of the eye. X 38. 



458 



