Hippocampus

Hippocampus: A specialized cortical area rolled into the medial temporal lobe. The hippocampus plays a critical role in the consolidation of new memories of facts and events. Anatomically, it has three subdivisions (until recently, usually referred to collectively as the hippocampal formation rather than the hippocampus), from within outward as follows:

Dentate gyrus: In cross section, one of two interlocking C-shaped strips of cortex (the hippocampus proper is the other). Afferents from entorhinal cortex, efferents to hippocampal pyra­midal cells.
Hippocampus proper: (also called cornu ammonis, or Ammon's horn). Afferents from the dentate gyrus and septal nuclei, efferents to the subiculum and septal nuclei.
Subiculum: A transitional zone between the hippocampus proper and entorhinal cortex, the subiculum receives afferents from the hippocampus proper and is the principal source of efferents from the hippocampus in general.