Arhinencephaly, a malformation of the brain, is closely related in its pathologic process and genesis to cyclopia. Though not particularly common, it appears in a fairly wide range of variations. The case here reported is of special interest because there were among other anomalies an extreme degree of eversion of the end-brain and a relative reduction in the size of the basal ganglia. REPORT OF A CASE History. —A girl, born at full term by spontaneous delivery, became intensely cyanotic one hour after birth. Three hours later she was brought to the hospital. On examination there were intense cyanosis, moderate exophthalmos and tense fontanels. A lumbar puncture yielded frankly bloody fluid. The infant took feedings fairly well but did not gain weight; she died on the fourth day after admission. The mother of the infant was said to have received some injections. Wassermann tests of her blood, however, and those