The body of the fornix travels anteriorly and divides again near the anterior commissure. This structure gives existence to the corpus callosum, the septum pellucidum, and the fornix. The vesico-uterine pouch is close to the anterior fornix of the vagina. It runs as a sheet from the corpus callosum down to the fornix. In front of the foramen is the fornix and behind is the thalamus. It is near the posterior fornix of the vagina. Their ducts unite into a rather long sinus which open into the fornix conjunctiva. They are located at the ends of the anterior arches of the fornix. The crura (posterior pillars) of the fornix are prolonged backward from the body. Smear from posterior fornix is used as control. This position aims the head of the penis at the vaginal fornix (posterior fornix). The fornix is part of the limbic system. Parity is associated with a significant increase in the length of the vaginal fornix. The fornix is a bundle of nerve tracts made of white matter. In Latin, the term "fornix" means arch or vault.