11Incest by a woman
(1)It is an offence for a woman of the age of sixteen or over to permit a man whom she knows to be her grandfather, father, brother or son to have sexual intercourse with her by her consent.
(2)In the foregoing subsection " brother" includes half-brother, and for the purposes of that subsection any expression importing a relationship between two people shall be taken to apply notwithstanding that the relationship is not traced through lawful wedlock.