The Vesica Pises is made by linking two circles together, bringing the outside edge of each to the midway point of the other. The almond shaped center of the image is call a madorla (Latin for almond) When the Vesica Piscis is viewed horizontally however, the mandorla becomes a different sort of passage, the birth passage.  The pointed oval is the universal symbol of the Divine Feminine and in this context the Vesica Piscis is the vulva of the Goddess surrounded by the crescents of the waxing and waning moon.