THE large number of head injuries observed in battle casualties provides the best material for study of the representation of various areas of the retina in the cerebral cortex. Few contributions have been made from injuries sustained outside of war periods.
Experimental determination of field defects by induced injuries is not feasible, for obvious reasons. One, therefore, must depend on lesions of the brain in human subjects studied at operation or at necropsy. From patients so studied one can draw certain conclusions concerning those who do not come to operation or to necropsy.
The two most significant papers on the subject are those by Holmes and Lister,1 in 1916, and by Holmes,2 in 1918, in which they reported their studies of disturbances of vision by cerebral lesions observed in British casualties in World War I.
Henschen,3 in 1900, had pioneered with pathologic studies showing that the visual