As the name suggests, a brown bird with a horn (casque) on its bill. Males are more brightly marked, with a white face and light orange-brown underparts. Females are darker brown with an almost black face. Both sexes have pale bills with small casques and a patch of bare blue-gray skin around the eye (smaller and darker in females). Inhabits lowland and hill forests. Gives high-pitched, rather raptor-like screams.