Ultrastructure of cytotrophoblast cells of the agouti subplacenta in midgestation. (A) Cytotrophoblasts (cyt tr) rest on a basal lamina (bl) that is closely apposed to the endothelium of a fetal capillary. On the other side they are in contact with the syncytiotrophoblast (syn tr). (B) Large intercellular spaces (ics) occur between the cytotrophoblasts. (C) Detail showing abundant rough endoplasmic reticulum and numerous electron dense inclusions. Scale bars: 2 μm (A); 3 μm (B); (C) 200 nm.