Role of Siamese cat's crossed and uncrossed retinal fibres in pattern discrimination and interocular transfer.

Siamese and ordinary cats were monocularly tested in pattern discriminations and visual perimetry following unilateral optic tract section. While ordinary cats exhibited similar performances when tested with either eye, in Siamese cats the eye contralateral to the sectioned optic tract was practically blind. Thus, the Siamese cat's uncrossed visual pathways are not able to subserve either form or ambient vision. The nature of such a loss is discussed.