No. 383.] BASIS FOR A THEORY OF COLOR VISION. 845 
(2) If the ray were unpolarized, there would be the same 
maximum stimulation at R as before, with a diminution of the 
stimulation on either side, above and below, but all the fibrils 
in the same transverse plane would be stimulated alike, because 
all the fibrils would be at right angles to at least one plane of 
vibration. We may, therefore, represent graphically the effects 
produced by a ray of polarized or unpolarized red light by the 
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Fic. 6. — Vertical section of ocellus II of Lycosa. The section is cut at right angles 
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curve v (Fig. 9, A). It should attain its maximum height a little 
way from the base of the cone and gradually fall to zero towards 
the apex, where the fibrils are too short to be affected by long 
ether waves. The curve will fall away more rapidly at the base 
of the cone because the long fibrils are supposed to terminate 
abruptly there. 
(3) Similar results should be produced opposite V on stimu- 
lation with violet light, and of course similar results would 
again be produced at any intermediate point between R and V 
by using monochromatic light of a corresponding intermediate 
wave length. The stimulation curve for violet light would have 
