Herpes zoster ophthalmicus presents an interesting problem. Although the disease was known to physicians of antiquity, their ideas concerning the disorder were obscure. They described, in considerable detail, the characteristics of the disease, but their interpretations were brief. The disease was known as zoster to the Greeks, and Pliny, a Roman, is said to have been the first to apply to the eruption the denomination of zona. From these ancient times to the early nineteenth century the literature is scant on the subject. Mahlis, in 1818, suggested that the eruption of herpes zoster followed the distribution of nerves, and Parrot, in 1856, noted that the eruption, like pain, developed along the course of branches of nerves, most frequently superficial, and that it was here that the neuralgias ordinarily manifested themselves. This was proved in 1861 by von Bärensprung. Hutchinson, in 1866, and Bowman, in 1867, were the first to describe