BLEPHARISMA INTERMEDIUM: ULTRAVIOLET RESISTANCE OF PIGMENTED AND ALBINO CLONES.

An albino mutant of Blepharisma intermedium is much more sensitive (on the basis of time to regeneration of transected cells) to short-wavelength ultraviolet radiation than the wild type (containing a reddish pigment) from which the mutant derived. In the wild type, absorption of ultraviolet light by the pigment present in the outer surface of the cell presumably reduces the intensity of the radiation impinging on the vulnerable interior.