The hemipenes are located in the invaginations at the base of the tail and are held in place by a retractor muscle. The functional surface of the [[Hemipenes|hemipenis]] is the lumen of this cavity. The paired openings of the [[Hemipenes|hemipenes]] are just inside the mucocutaneous junction and one fourth of the way medial from the lateral corners of the [[Vent|vent]]. For copulation they evert through the [[Vent|vent]]. The [[Hemipenes|hemipenes]] may have protuberances that help grip the female and there is a surface groove, the sulcus spermaticus, involved in the propulsion of semen. | The hemipenes are located in the invaginations at the base of the tail and are held in place by a retractor muscle. The functional surface of the [[Hemipenes|hemipenis]] is the lumen of this cavity. The paired openings of the [[Hemipenes|hemipenes]] are just inside the mucocutaneous junction and one fourth of the way medial from the lateral corners of the [[Vent|vent]]. For copulation they evert through the [[Vent|vent]]. The [[Hemipenes|hemipenes]] may have protuberances that help grip the female and there is a surface groove, the sulcus spermaticus, involved in the propulsion of semen. |