THE central part of the face and the forebrain are closely connected in early development, and when midline facial defects occur, there is often concomitant maldevelopment of the anterior part of the brain.1 It was at first thought that the cerebral anomaly consisted of a lack of development of the olfactory bulb, tract, and cortex (arhinencephaly); but the abnormality is now known to be more extensive, with failure of division of the forebrain into lobes and ventricles. For this condition the terms holotelencephaly and alobar holoprosencephaly have been used. Brucker et al1 did not think that these terms adequately covered all the possible varieties of lesion which may occur and suggested as a descriptive title median cerebrofacial dysgenesis. DeMyer and co-workers2 pointed out that if the median facial abnormalities were associated with hypotelorism, a holopresencephalic brain was an invariable accompaniment. We feel that the name given to