The claustrum in the dog brain.

The structure of the claustrum was studied in the dog brain using Weigert's, Klüver-Barrera's, Manns' and Nissl's methods. It consists of two main parts arranged one above the other. The dorsal part is situated in the depth of the neocortex and extends from the gyrus orbitalis to the gyrus compositus posterior. The ventral part of the claustrum underlying the olfactory cortex continues from the cuadal fragments of the olfactory peduncle to the entorhinal area, where it fuses with its deep layers. The claustrum can be regarded as a fragment of a bigger cellular formation present in different parts of the hemisphere.