HARTMAN — BROWN MUTATION IN OPOSSUM 
149 
The iris of the eye was also examined in the three mutants as well 
as in the normal controls (grays). The iris is generally invisible, but 
in the bright sunlight it appears as a narrow marginal band. In the 
gray phase the iris is deeply pigmented, almost black; in the cinnamon 
mutants the iris is light, blending from the very light inner margin to a 
distinct brown at the periphery where it disappears under the eyelid. 
All pigmented areas of the McNeill mutants, therefore (hair, scales 
of tail, ears and iris), have the brown color. 
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The University of Texas^ Austin, Texas, 
