Lissencephala /(lĭs`sĕn*sĕf"ȧ*lȧ)/

Lis·sen·ceph·a·la

Lissencephala

n. pl.
  1. A general name for all those placental mammals that have a brain with few or no cerebral convolutions, as Rodentia, Insectivora, etc. (Zool.)