Data over the ascending and descending parts of the recent sunspot-cycle from widely distributed ionosphere stations have been utilized to trace the geographic features and nature of the spread-F equator in low latitudes. Indications are that the spread-F equator is nearly a great circle, approximately parallel to the geomagnetic equator, but swinging, during an 11-year period, through an angle of plus and minus 25° of latitude, about an axis through Japan and Argentina. The two fundamental types of spread F (polar and equatorial) and forked F are discussed.