Arterial calcification; fetus 36 weeks. a: H&E stain showing festooned cortex with adhesion of the leptomeninges to the cortical surface The thickened, vascular meninges dip into the sulci (arrows). b: Reticulin stain showing thickened pial collagen and increased leptomeningeal vascularity. The pial surface is partly buried in masses of heterotopic cortex (arrow). c: Surface artery with confluent calcification in the wall. The intima is thickened and fibrous with a very reduced lumen. d: The hippocampal cortex is normal.