“…Surprisingly, a small, though distinct, reti nal pathway terminates within the medial terminal nucleus of the squirrel monkey. With the exception of one report [Gillilan, 1941], previous descriptions of the AOS in primates have failed to identify either the nucleus [Giolli, 1963;Lin and Giolli, 1979] or any retinal input to the region [Giolli, 1963;Campos-Ortega and Glees, 1967;Campos-Ortega and De V. Clüver, 1968;Campbell, 1969;Tigges andTigges, 1969, 1970;Giolli and Tigges, 1970;Hendrickson et al, 1970;Tigges and O 'Steen, 1974;Tigges et al, 1977;Lin and Giolli, 1979]. Recently, however, a small superficial la belled retinal pathway was described as extending from the lateral terminal nu cleus toward the medial terminal nucleus [/taya and Van Hoesen, 1983], although there was no indication that the retina in deed terminated within the medial termi nal nucleus.…”